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An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997 (1997)

Chapter: 6 Materials Science and Engineering Laboratory

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Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
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Chapter 6

Materials Science and Engineering Laboratory

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

PANEL MEMBERS

James E. Nottke, E.I. Du Pont de Nemours & Co., Inc. (retired), Chair

Robert L. Brown, Gillette Company

Stuart L. Cooper, University of Delaware

John A. S. Green, Aluminum Association

James D. Idol, Rutgers, The State University of New Jersey

Lawrence C. Kravitz, Allied Signal, Inc. (retired)

Frederick F. Lange, University of California at Santa Barbara

Merrilea J. Mayo, Pennsylvania State University

Donald E. McLemore, The Dow Chemical Company

Boyd A. Mueller, Howmet Corporation

Donald R. Paul, The University of Texas at Austin

Dennis W. Readey, Colorado School of Mines

Walter L. Winterbottom, Ford Motor Company (retired)

Submitted for the panel by its Chair, James E. Nottke, this assessment of the fiscal year 1997 activities of the Materials Science and Engineering Laboratory is based on site visits by, and a meeting of, the panel on April 9–10, 1997, and on the annual report of the laboratory.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

LABORATORY-LEVEL REVIEW

Laboratory Mission

The Materials Science and Engineering Laboratory (MSEL) stated that its mission is to stimulate more effective production and use of materials by working with suppliers and users to assure the development and implementation of the measurements and standards infrastructure for materials.

The laboratory mission directly supports NIST's mission. All manufacturing relies on understanding materials and the use of materials measurements and standards; as a result, the work of this laboratory is crucial to U.S. competitiveness in major industry segments such as transportation, communications, and materials processing. The Materials Science and Engineering Laboratory works with the components of the supply chain that can make the best use of advances in measurements and standards and ensures that the latest technology is made available to those components. The “Strategic Plan for the Materials Science and Engineering Laboratory” issued in June 1996 has stimulated debate and discussion on the important issue of which areas the laboratory will maintain as world-class efforts in support of its mission.

Technical Merit and Appropriateness of Work

In general, the technical merit of the work is excellent throughout the Materials Science and Engineering Laboratory. The programs are consistent with the mission and take advantage of NIST's unique measurement and standards capabilities. Projects are appropriately directed toward the needs of U.S. industry and use the abilities of laboratory personnel to make a difference. The current process of determining program termination and initiation consistently produces an improved portfolio of programs. One example of successful implementation of this process is the recent reinvention of the Materials Reliability Division, which has made a complete transition. This division has shifted from a focus on cryogenic materials to a broad and balanced array of materials programs, such as the current work on ultrasonic characterization.

Producing new SRMs from new measurement technologies is integral to the laboratory's mission, and the panel is pleased that this process is occurring in all divisions. As in any good research laboratory, some recently initiated programs cannot yet be assessed. Also, some staff members have moved into new areas, and it is still unclear if they will be able to rise to their previous levels of contribution and leadership. Each of the division reports presented here addresses technical merit in more detail.

The panel found that most completed programs had proved effective; the results provided answers to key questions, delivered successful new measurement tools, or heightened fundamental understanding. The effectiveness of the laboratory's current work is enhanced by several programs that cut across divisional and laboratory boundaries. This cross-fertilization allows improved use of equipment and experience, broadens staff expertise, and encourages the formation of new interdisciplinary efforts. Within the Materials Science and Engineering Laboratory, the Center for Theoretical and Computational Materials Science (CTCMS) is a good example of a novel organizational arrangement. The CTCMS is highly productive because it allows a small group of experts to serve the entire laboratory.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

Laboratory staff members diligently disseminate information about results and work-in-progress through all the conventional routes: publishing in NIST documents and peer-reviewed journals, presenting at scientific meetings, giving seminars, participating in workshops, hosting visitors, and responding to inquiries. The laboratory has established a site on the World Wide Web and has begun to develop mechanisms that use the Internet for dissemination. The Materials Science and Engineering Laboratory aims to be the preferred source for all information about materials-related measurement technology and standards, and a high-quality Web site will help the laboratory achieve this objective.

Industrial Impact

Several good examples of industrial impact are incorporated into the divisional reports below. The active participation of industrial personnel in NIST research and the corresponding financial commitment of industrial research partners to NIST programs indicate that industry holds the Materials Science and Engineering Laboratory in high regard and values the output of its programs. This laboratory holds more than one-third of the patents granted to NIST personnel over the last decade and is involved in about one-quarter of the active NIST Cooperative Research and Development Agreements (CRADAs). These two statistics also attest to the quality and value of the laboratory 's activities.

Industry tends to be secretive about current advances in materials, and this reticence makes it difficult to thoroughly assess recent impact. It is much easier to note that the laboratory had a major effect on the industry one or two material generations ago, but past successes do not ensure the relevance of current programs. There is anecdotal evidence that U.S. companies continue to respect and use the output of laboratory programs. For example, people in the ceramics, metals, or polymer industries in search of general information on measurements and standards usually ask their trade associations first and then turn to NIST. When a trade association needs such information, it turns directly to NIST.

Laboratory Resources

The Materials Science and Engineering Laboratory receives most of its support from internal NIST sources. These include NIST Scientific and Technical Research and Services (STRS) funding, which is a direct appropriation from Congress, and funding from support of other NIST units such as the Advanced Technology Program (ATP). Competence Funding from the Director's Office, which is designed to build expertise in key areas of future industrial needs, is counted in STRS. The final source of support is a combination of external funding from other federal agencies (OAs), nonfederal government entities (NF), and cooperative research and development agreements (CRADAs), income from measurement services such as Standard Reference Materials (SRM) production, and other miscellaneous expense and income.

Funding sources for the Materials Science and Engineering Laboratory excluding the Reactor Radiation Division (in millions of dollars):

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×
 

Fiscal Year 1996

Fiscal Year 1997 (estimated)

NIST-STRS

31.4

31.8

ATP

3.1

3.1

OA/Reimbursable

7.4

7.4

Total

41.9

42.3

At the moment, the total staff of the Materials Science and Engineering Laboratory includes 292 full-time permanent (FTP) positions, including 251 for technical professionals. There are also 450 guest researchers.

The dependence on OA funding has declined and is at roughly 15 percent of total budget, a level laboratory management considers appropriate. The overall MSEL budget is adequate but tight, with the exception of the Metallurgy Division, where funding is extremely tight. In this division, budget reductions have prevented the hiring of sufficient new staff to maintain all areas of expertise, and some capabilities are gradually being lost.

As detailed in the divisional reports that follow, the equipment and physical plant are considered adequate for the current staff and research portfolio, but the capital designated for building renovations and research facilities is not enough for the future needs of the laboratory.

Laboratory Planning

The laboratory's strategic plan describes its vision, values, goals, and objectives. The laboratory has also implemented a new project tracking system that is useful in examining planning issues. The next level of planning is carried out at the division level and is outlined in the divisional assessments.

The current planning process adequately anticipates and resolves issues related to budgeting, staffing, program direction, and technology. In general, planning effectiveness is often measured by how well an organization supports the plan, follows it, and adjusts it in response to new information. Across the MSEL, each of these tasks is handled appropriately by the planning process.

The plan and the process continue to evolve, but the panel notes two areas in which this evolution is incomplete. One concern is that the laboratory sometimes does not define explicit outcomes and deliverables at the beginning of each program. Such output definition makes the research more goal oriented and allows potential industrial beneficiaries to buy into the program, which then enhances technology transfer. Another concern is that consideration of the life cycle aspects of new materials and processes are not always incorporated into the planning process. Life cycle analysis of new materials has become an integral component of material selection in industry.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

DIVISIONAL ASSESSMENTS

Ceramics Division
Mission

The Ceramics Division stated that its mission is to provide measurement methods, standard reference materials, and standard reference data for materials producers and users; to assist U.S. industry with the development and implementation of the cost-effective design and manufacturing of reliable ceramic materials; and to perform research which leads to basic understanding and predictive models relevant to the processing and performance of advanced ceramic materials.

This mission statement accurately reflects the substance and objectives of the activities under way in the Ceramics Division. The seamless manner in which projects increasingly traverse divisional boundaries indicates that the mission of the division is well integrated with that of the MSEL as a whole. In addition, the panel approves of the explicit emphasis on standards-related work and endorses the division 's extensive activity in this area. Divisional personnel appropriately see themselves as facilitators, rather than solvers of mundane problems or inventors of new materials.

Technical Merit and Appropriateness of Work

The Ceramics Division has a strong reputation for excellence and is now one of the largest ceramics research groups in the United States. Nonetheless, NIST cannot be a leader in all areas of ceramics research. The division's senior personnel have accordingly chosen to concentrate available resources on areas in which the division can have a unique impact. Consistent with the overall NIST mission, they are targeting areas with a clear link to industrial needs on a national scale and that relate to the production of standards, data, and reference materials. The programs pursued in this division are of high quality. Some examples of the technically important work being considered are described below.

The Phase Equilibrium Program currently focuses on materials for wireless and microwave communications. These fields support a rapidly growing industry, and discovery of improved dielectric materials is essential to its continued progress. However, this industry is composed mainly of small companies ill equipped to carry out the necessary basic research in house. Therefore, the Ceramics Division 's generation of phase equilibria data to facilitate development of new materials provides key technological support for this burgeoning industry. This program is unique partly because phase equilibria research is no longer fashionable and therefore difficult to fund at universities. In addition, researchers at NIST-Boulder have world-class expertise and facilities for the high-frequency electrical characterization of these materials, so close collaborations between Gaithersburg and Boulder on fabrication and characterization will rapidly provide new materials for industrial applications. Such advancements will benefit both the communications companies that use the materials and their suppliers, such as Trans-Tech, Inc. This major manufacturer is near the Gaithersburg campus and has collaborated on materials testing through a CRADA with this group.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

The Coatings Program reflects NIST's important role as a facilitator of industrywide communication. The properties of the plasma-deposited coatings used by a wide variety of engine manufacturers strongly depend on the coating microstructures. Methods to accurately predict and measure these microstructures can therefore greatly improve engine performance. The Coatings Program is not a large research effort in this field, but the work done at NIST is a nucleus that allows industry and university scientists to share information on coatings and properties. The achievements of this group are an excellent demonstration of how a relatively modest expenditure can have significant industrial impact.

The Ceramic Grinding Consortium is a group of industrial practitioners and industry and university researchers working cooperatively with NIST to establish data on the optimum machining conditions for advanced ceramics. Because there are so many interesting materials and variables in this field, no single organization could hope to gather a complete and useful set of information in a reasonable period. By coordinating research activities through the consortium, the Ceramics Division has had a major impact on improving industrywide understanding of ceramics machining.

The recently hired leader of the powder characterization project greatly enhances the group's reputation and is also steering it in a new direction. The focus is on how ceramic powders behave during the forming processes. Proposed research topics, such as dispersion of dense suspensions and replacement of mercury by a nontoxic alternative for porosimetry, reflect the concerns of industrial users of ceramic powders.

The fundamental design methodology for brittle materials was essentially established at NIST. Currently, the research on creep deformation of ceramics and the corresponding development of standard test techniques are further examples of this division's continuing leadership in improving understanding of the mechanical behavior of ceramics. Within this field, the Theory and Modeling Program has used computer simulations to relate the mechanics and the properties of polycrystalline materials. These simulations are a potential methodology for materials design. They will certainly assist in the development of high-temperature structural components and in the use of functional inorganics in electronic and optical devices. In addition, the division's continued work on the mundane but absolutely necessary task of establishing mechanical properties standards is widely appreciated within the technical community.

The panel had previously expressed some concern that ceramic processing is a vertically integrated process and that the division's work on characterization of starting powders would have no impact if the effects of powder characteristics were not integrated into subsequent processing steps. Therefore, the panel strongly supports the new Ceramic Processing Characterization Consortium and the effort to incorporate understanding of powder characteristics into later steps in ceramics processing. The specific directions taken by this consortium will interest many members of the ceramics industry.

The division disseminates information about its programs through sponsored workshops (such as the recent one on materials for wireless communication), periodic meetings held by various consortia, staff presentation of papers and attendance at professional meetings, and participation of division personnel on various interagency and standards committees. However, the fastest-growing information dissemination mechanism is clearly the Web.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×
Industrial Impact

The long-term effectiveness of some divisional programs is difficult to assess. However, the significant number of industrial partners for various projects suggests that companies do expect Ceramics Division research to produce important and relevant results. Such direct involvement in divisional activities should (and does) result in an efficient and effective exchange of information. Companies that actively participate in collaborative research projects are using a mechanism of immediate technology transfer far more effective than reports, presentations, or technical papers. However, it is unclear how the division might ensure equally effective dissemination of information to firms that do not collaborate directly with NIST.

Quantifying the impact of the division's programs on industry is also difficult. One measure is the frequency with which NIST-developed standards or data are bought, referenced, and used by industry. Another is whether industrial partners continue to participate in CRADAs or consortia.

There are isolated but notable instances of high-quality technical work with minimal industrial impact. One example is the division 's effort to provide rational design criteria for brittle materials, particularly structural ceramics. The resulting standards have generally not been adopted by the ceramics industry and are used only rarely by the relevant user industries. This is partly because there are no brittle materials design classes in the standard engineering curriculum. The resulting lack of experts in this area has been one of the largest impediments to broader application of structural ceramics and has retarded that industry's growth. Understanding why the seminal work at NIST did not have a greater impact might suggest better methods of disseminating information and working with industry partners in the future.

Resources

Funding sources for the Ceramics Division (in millions of dollars):

 

Fiscal Year 1996

Fiscal Year 1997 (estimated)

NIST-STRS

9.6

9.6

ATP

0.8

0.7

OA/Reimbursable

1.3

1.6

Total

11.7

11.9

The staff of the Ceramics Division includes 63 FTP positions, of which 53 are for technical professionals. There are seven non-FTP/supplemental personnel, including full-time temporaries, postdoctoral students, faculty, and other part-time workers.

The division has made a conscious effort to decrease the percentage of its work supported by outside agencies. New OA funding is only accepted for projects consistent with the divisional mission. This strategy allows the division to select programs based on technical merit and potential impact, rather than on the current goals of other federal agencies or specific industrial

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

firms. If the direct federal funding of the NIST Laboratory programs declines, this freedom may well be curtailed.

Tours of the laboratories demonstrated that the equipment available to the scientists in this division is adequate. As the number of personnel is not increasing, the current space allotment is also sufficient. The Ceramics Division has access to some special facilities, including the laser ablation mass spectrometer, the microtribology laboratory, the nuclear magnetic resonance (NMR) imaging facility, beam lines on the NIST reactor and on synchrotron light sources, and a host of state-of-the-art mechanical testing equipment. However, the lack of certain other facilities unduly constrains technical activities. In particular, the absence of cleanroom space for films and optoelectronics that is vibration free and dust free severely limits the scope of the research in this technologically critical area.

Planning

From discussions with division management, it appears the division chief and the group leaders base joint decisions about projects on feedback from workshops and other interactions, the interests and expertise of the staff, and predictions on future needs of the ceramics industry. This planning process allows for continual restructuring of division programs. The effectiveness of this process is demonstrated by the revitalization of the effort on tribology. Since the last assessment, the focus has sharpened, new facilities have been funded, industrial interest is stronger, and the enthusiasm among group personnel has increased. In general, the division chief's current reorganizational efforts have resulted in a stronger, more focused set of projects. The panel applauds the strong leadership, enthusiasm, and sense of direction he brings to the division.

This year, there will be a new emphasis on functional ceramics rather than on structural materials. The focus will be on thin films in particular, as is demonstrated by the assignment of 11 staff members to the work on thin-film preparation and characterization. In addition, the powder characterization effort will be broadened to include much more of the ceramic powder manufacturing process. This expansion reflects a change of leadership for this group and a corresponding shift in interest and expertise. The major thrust on functional (electronic) ceramics with the emphasis on thin-film characterization and properties takes the division in an important new direction. However, the panel believes that the specific goals and expected outcomes of this effort are too broad and vague. Throughout the division, integrating modeling efforts with experiments will also be emphasized in the coming year.

Materials Reliability Division
Mission

The Materials Reliability Division stated that its mission is to develop measurement technology and provide standards to improve the quality, reliability, and safety of engineering materials.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

The division's activities directly support the programmatic thrusts of the Materials Science and Engineering Laboratory and are consistent with the mission of NIST. The scope of the technical work in this division is appropriately limited to ensure that the resources and personnel allotted to each effort remain above the critical level. The areas chosen for specialization complement other national efforts appropriately without duplicating them and address nationally important issues in measurements and standards.

Technical Merit and Appropriateness of Work

The panel found that the projects undertaken by the division generally are of high technical merit. These efforts include the extension of ultrasonic measurement technology to the characterization of material microstructure features such as texture, grain size, strain, dislocations, and recrystallization; the use of electron microscopy for nanoscale measurement of flaws in electronic packaging; and development of measurement technologies required for real-time control of welding and thermomechanical processing of structural materials.

These programs are funded internally and appropriately address the measurement technology and standards requirements defined by the major MSEL program areas. The panel endorses the current array of projects but notes a few areas in which division efforts fall short. For example, the outputs expected from the efforts in acoustic transducer development are not sufficiently defined. Consultation with physical metallurgists would assure that the expected measurement capabilities are targeted to maximize both their impact on industry and their ease of adoption. The number of microelectronics packaging companies that the division partners with could be higher, and the division lacks an automotive original equipment manufacturer partner to serve as a launch customer for the weld characterization measurement technology. Industrial users would benefit if NIST personnel developed an application note describing the generic weld parameter model. In this field, the division has a good opportunity to partner with the Nuclear Regulatory Commission on weld characterization for nuclear reactor vessels. Finally, the MSEL is not placing enough emphasis on endorsing and funding activities that protect and enlarge U.S. influence in the international standards community, such as the effort of the Materials Reliability Division to maintain an American standard in acoustic blocks.

The yearly technological advancements made by this division indicate to the panel that projects are effectively organized and efficiently executed. In addition, the division devotes considerable effort to disseminating the results of its programs to industrial users through NIST personnel's leadership and participation in standards-setting committees, conferences, and workshops as well as through staff publications. Division management is considering requiring that hands-on technical notes be produced for each measurement development effort. Such notes would guide users with modest experience in the applications and limitations of the technique. The panel supports this approach. Such documentation would assist industry in adopting new measurements and standards procedures and support the division's commitment to a highly effective dissemination program.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×
Industrial Impact

The division's current mix of projects is designed to balance efforts with short-term goals against programs that develop the skills necessary to address future issues in materials reliability. The work on a national center for Charpy standard materials and the planned production of a U.S. acoustic block standard are both designed with immediate industrial impact in mind. If the planned Nuclear Regulatory Commission initiative to measure the remnant lifetime in nuclear power reactors is successful, it will also have a substantial effect nationally in the near future. The impact of the efforts on electronic packaging will be felt continuously over the next 2 to 3 years, whereas the work on advanced acoustic sensors is designed to answer the longer-term needs of industry. This broad portfolio of efforts promises to produce a steady stream of outputs over the next 5 years.

The division's measurement technology efforts address the needs of major sectors of industry, and therefore the division's contributions can be expected to have substantial impact. However, because so many factors influence the successful adaptation of technological advancements, it is difficult to assess the impact, economic or otherwise, of this division's work.

Resources

Funding sources for the Materials Reliability Division (in millions of dollars):

 

Fiscal Year 1996

Fiscal Year 1997 (estimated)

NIST-STRS

3.8

3.8

ATP

0.7

0.7

OA/Reimbursable

0.9

0.8

Total

5.4

5.3

The staff of the Materials Reliability Division includes 32 FTP positions, of which 28 are for technical professionals. There are 10 non-FTP/supplemental personnel, including full-time temporaries, postdoctoral students, faculty, and other part-time workers. The technical staff members have the laboratory space and equipment they need to carry out divisional programs.

The laboratory staff is of high caliber and adequate for the tasks undertaken with the current level of funding. Augmenting the resident staff with visiting researchers and National Research Council postdoctoral students provides a stimulating mix of expertise and effectively hedges against the risk of a downturn in OA funding; currently, however, outside sources such as OA grants provide only about 15 percent of the division's budget. This OA funding is used to support tasks that complement internally funded projects and extend the skills of the staff. The planned initiative with the Nuclear Regulatory Commission will increase the division's dependence on outside agencies. But this is also a unique opportunity to coordinate several areas of expertise in a concerted attack on a single measurement technology challenge. To ensure that this temporary influx of support does not produce the usual difficulties associated with program

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

restructuring and personnel reassignments, management plans to supplement NIST staff with visiting researchers who will depart at the conclusion of the project.

The laboratory equipment is adequate to carry out the tasks currently under way. The effectiveness of the equipment is greatly enhanced by the excellent laboratory facility, which has greatly improved in the past year. Management is to be commended for establishing an efficiently designed and superbly equipped development environment.

Planning

The division planning process is designed to address long-range issues such as how to build the skills base needed to handle future standards needs, as well as shorter-range issues, including product dissemination and project selection and execution. The central objective of this comprehensive planning effort is to maximize the capability of the limited number of staff members in contributing to advances in measurement technology and standards development as prescribed in the laboratory mission. The planning process has proven effective in reorienting the division from a major commitment to cryogenics to the four current focus areas: intelligent processing of materials, ultrasonic characterization of materials, micrometer scale measurements for materials evaluation, and support for the national standardization of Charpy measurements. Continuation of integrated planning will enable the division to better meet future requirements in these evolving fields.

The planning for skill-base development has matured nicely, allowing the division to pay more attention to defining the results expected from various projects. The best plans usually describe both the substance of the output and the form in which it will be disseminated. For example, information about a new measurement technique or a standard sample might be packaged as a recommendation, a how-to report, or a video demonstration.

Polymers Division
Mission

The Polymers Division stated that its mission is to provide the measurement methods, standards, and concepts of material behavior needed for the efficient processing and use of polymers by those U.S. companies that produce, process, or use polymers in important aspects of their business.

The breadth of this mission statement is consistent with the diversity of the industry served by the Polymers Division. This division clearly cannot have a research presence in all of the wide range of areas that encompass polymer technology, but the programs currently in place represent a reasoned and logical cross-section of topics of critical importance and general interest.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×
Technical Merit and Appropriateness of Work

The Electronic Packaging and Interconnects Program continues to focus on developing measurement tools that improve understanding of the properties and performance of the polymers used in microelectronics applications. The goal of this work is to lower the costs and improve the performance of packaging and interconnects. Recent contributions of this group on issues that pervade this industry include studies on the effects of moisture and the physical state of water in ultrathin films and at interfaces; methods for accurate measurement of z-axis coefficients of thermal expansion; work on the contrast between physical properties of thin, constrained films and the behavior of these materials in bulk form; and efforts on thermal diffusivity in films and at interfaces. New programs in this area focus on measuring residual stress and the aging of electroluminescent polymers. The division currently has no programs on thermo-oxidative stability or on physical aging of polymers in microelectronics, areas that might be of significant interest to industry.

The scientific goals of the Polymer Blends and Processing Program include establishing expertise in static and kinetic aspects of phase behavior in polymer blends, studying the effects of shear flow on mixing and phase separation, using reactive processing to promote compatibility, and advancing techniques for online determination of temperature and structure. The scientists in this group have developed several novel measurement systems that provide NIST with unique capabilities in blend and process research. Program objectives are further enhanced by the development of new measurement tools, including those involving light and neutron scattering; neutron reflectivity; x-ray scattering; birefringence; rheology; and atomic force, transmission electron, and phase contrast microscopy. The panel was particularly impressed by the start-up of a new program in polymer-filler interactions that uses a variety of technologies. Proper staffing and careful selection of specific systems should enable the scientists in this group to make use of the techniques available at NIST to gather much important and fundamental information about these interactions. However, it is necessary to work closely with industry to ensure that the efforts in this field focus on areas with practical applications.

The field of composite technology is broad and complex, but the Polymer Composites Group at NIST has done a good job of selecting topics that match the skills and capabilities of its staff and facilities. This program continues to focus on technologies related to liquid composite molding, in the belief that this fabrication technology is critical to the nondefense-related materials industry. Recent accomplishments include the development of in-process sensors for fast-cure methods; development of new, broadly applicable interfacial test methods; and development of a model for flow in heterogeneous porous media to help guide the design and operation of pre-forms and molding processes. Areas in which the composites program staff 's expertise has not yet been utilized include nanocomposite systems and performance criteria in composites application. In the former field, industrial research appears to have peaked, but a breakthrough could still be achieved. In the latter area, the study of issues such as durability, fatigue life, and environmental stability is incomplete.

The Polymer Characterization Program aims at developing new methods for measuring physical properties of polymer systems, providing reliable data on these subjects, and supplying SRMs to U.S. industry, research laboratories, and federal agencies for calibrating methodologies and instruments used in measuring and comparing polymer properties, processability, and performance. Within the constraints of its budget, this program addresses some of the most

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

important and relevant topics at the interface of industry needs and state-of-the-art research in polymer characterization and analysis. The synergism of permanent NIST staff, visiting scientists, and postdoctoral staff produces the high level of expertise necessary to address the current programmatic thrusts of this group and to perform needed research at the frontiers of polymer technology. The group is currently focusing on molecular structure delineation, solid-state morphology, and the influence of structure and morphology on mechanical and thermal properties.

One project aims to exploit and refine the use of matrix assisted laser desorption ionization (MALDI), a versatile tool for determining the molecular weights of synthetic and natural polymers. Along with the progress made by recent NIST efforts in refining size-exclusion chromatography, MALDI could provide much faster and more precise polymer molecular-weight data than gel permeation and earlier classic techniques such as light scattering and osmometry. Industry also needs polyethylene and polyolefin molecular-weight standards to address metallocene-derived and other new commercial polymers with novel backbone architectures.

The use of nuclear magnetic resonance (NMR) techniques to characterize polymer structures is also especially noteworthy and could produce an effective tool for characterizing polymer chain branching and related morphological and physical property effects. In combination with MALDI, this might offer significant time savings in characterization of the polymer structure and morphology that result from processing variations as well as from new catalysts now being introduced commercially, such as metallocenes and other geometrically selective catalyst combinations.

The small-angle x-ray scattering (SAXS) facility provides a powerful method to determine polymer conformation and structural subtleties (including block structures, thickness orientation in films, and effect of melt shear on the morphology of molded parts) that are not observable with other techniques. In conjunction with the Advanced Polymer Participating Research Team at the National Synchrotron Light Source, NIST SAXS has a polymer characterization capability not found elsewhere.

The project on electron microscopy techniques for polymer imaging includes cryogenic transmission electron microscopy (Cryo-TEM), a technique for imaging polymers in solutions and in vitrified solvent media. This method, and others in this program, improve the understanding of the morphology of various types of polymers substantially. These structures observed range from folded chain conformations of linear or slightly branched materials to dendrimers. The NIST initiative on dendrimer characterization will be of great help to industry in determining how dendrimers might be useful and how they could be tailored for commercial adaptability. The accompanying efforts using optical and atomic force microscopy balance the program and provide valuable parallel evaluations of the Cryo-TEM techniques with differing or identical polymeric materials.

The Dental and Medical Materials Program is a cooperative effort involving researchers from the Polymers Division, the American Dental Association Health Foundation, the National Institute of Dental Research, and the dental materials industry, as well as guest scientists from the U.S. Navy Dental Corps and U.S. and foreign universities. This group is to be commended for its vigorous pursuit of commercialization for the dental materials technologies developed in the laboratory. Noteworthy efforts have been made to disseminate the results on nonshrinking polymers and related matrix material synthesis to a broad range of specialty chemical companies.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

The effort in tissue engineering involving moldable bone grafts featuring calcium phosphate chemistry and biodegradable polymer composite systems is well matched to the division's expertise. The quality of the division 's work in cell microencapsulation is also high, although the rationale for NIST's involvement in this field is unclear. A more thorough understanding of industrial views on the future materials requirements for cell encapsulation technology might clarify the goals of this project. Work on fluorinated monomers and oligomers for chemically and mechanically stable dental restorative composites is necessarily formulation driven, but there are areas where thermodynamic and kinetic issues could be addressed more quantitatively. Solubility and phase diagram considerations would help organize the material selection and synthesis effort. More detailed physical characterization of the matrix materials through dynamic mechanical testing, x-ray scattering, and various microscopies would support rationalization of the ultimate property data.

Industrial Impact

The Electronic Packaging and Interconnects Group develops and maintains active collaborations with industrial partners through participation in workshops and distribution of publications such as “Electronics Packaging, Interconnection and Assembly at NIST: Guide and Resources.”1 This group effectively solicits input on emerging topics to determine which areas are particularly well suited to the expertise and facilities available at NIST. However, since this is a fast-moving industry, if the group does not receive sufficient feedback often enough, NIST is in danger of falling out of touch. To ensure that all companies can benefit from NIST work, this group focuses on issues that are pervasive in the industry and strives to balance a materials-neutral approach with the selection of systems that reflect either current or evolving industrial practices. The panel applauds this goal.

The current projects in the Polymer Blends and Processing Program focus on major problems relevant to a wide range of industries. The strength of the impact will depend on whether the group selects realistic systems of interest to industry and on how well program results are disseminated to private companies. For example, the blends program has recently improved its choice of model systems and is now making measurements on systems with broad commercial importance. In general, the mission and technical capabilities of NIST in this area are not appreciated broadly enough within the industry to have the desired impact. There are not enough ways for the staff to keep the community informed about Polymers Division programs or to get feedback on which issues of concern to industry could be most appropriately tackled by NIST. The present list of collaborators is limited, because it is unclear which companies would benefit from current programs and which people at these companies have the authority and technical knowledge to develop partnerships with NIST.

The Polymers Composites Group has diligently fostered and maintained collaborations with industry and academia, as demonstrated by programs with The Budd Company, Ford Motor Company, and Owens-Corning and by a workshop co-hosted with Ohio State University. This group has begun but not completed the process of soliciting input from companies through

1  

U.S. Department of Commerce, Technology Administration, National Institute of Standards and Technology, NISTIR 5817, National Institute of Standards and Technology, Gaithersburg, Md., 1996.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

workshops and other mechanisms to ensure that its program on liquid composite molding is tailored to meet industry's goals for composite implementation.

For the Polymer Characterization Program, division management is not placing enough emphasis on the importance of increasing information exchange and on the value of visitations to assure industry's appreciation of the program's potential commercial value.

In the Dental and Medical Materials Program, numerous coauthored publications demonstrate the intensity of the collaborations at the core of this group. The fact that each recent patent includes a coinventor from outside the Polymers Division indicates that the joint work is highly effective. At the moment, the division is working to clarify its role in the rapidly expanding field of tissue engineering. The effort currently focuses on a given cell system or disease state, rather than being directed to more generic issues such as membrane and protein transport through microporous media, molecular weight cutoff, or microporous membrane and microsphere technology.

Resources

Funding sources for the Polymers Division (in millions of dollars):

 

Fiscal Year 1996

Fiscal Year 1997 (estimated)

NIST-STRS

6.9

7.2

ATP

0.9

0.9

OA/Reimbursable

1.1

1.4

Total

8.9

9.5

The staff of the Polymers Division includes 47 FTP positions, including 41 for technical professionals. There are 13 non-FTP/supplemental personnel, such as full-time temporaries, postdoctoral students, faculty, and other part-time workers. In addition, there are over 100 guest scientists, 30 of whom are supported by funding from the American Dental Association and the dental industry.

The staff of the Electronic Packaging and Interconnects Program is well motivated and competent with respect to the targeted programs. However, there are not many staff members with significant industrial experience and credibility. The group's ability to hire such personnel might be hampered by NIST's usual expectations for employee publications and patents, which differ from more traditional industrial performance criteria.

The Polymer Blends and Processing Program is staffed by competent and enthusiastic professionals, and the permanent staff has attracted a cadre of talented and productive postdoctoral fellows and guest scientists.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×
Planning

A major challenge for the Polymer Composites Group will be the selection and implementation of a real-world experimental design to validate the emerging process models. It is unclear whether the magnitude of that task is currently well understood or clearly defined.

In the Polymer Characterization Program, the mechanism of identifying, choosing, and launching new projects is quite challenging, but the task appears to be receiving the appropriate attention from the director 's office and the senior staff.

Metallurgy Division
Mission

The Metallurgy Division stated that is mission is working closely with materials suppliers and users to develop the measurement and standards infrastructure needed in diverse technological areas. Both metals producers and users require measurements that enable more accurate prediction of materials performance, manufacturability, and long-term reliability. The division's programs address measurement-related needs within all industrial sectors that use metals and alloys.

Technical Merit and Appropriateness of Work

As industry continues to cut funding for fundamental research, the Metallurgy Division takes on an increasingly important role in contributing to the nation's basic understanding of technologies vital to the long-term success of several industrial sectors. The division has crafted its programs to deliver relevant, high-quality measurement methodologies and standards for the U.S. industrial base and is directly supporting the electronics, automotive, jet engine, and dental materials industries.

The panel considers several of the projects reviewed to be world class, and the modeling efforts of this division are a valuable national resource. The fundamental nature of these modeling efforts in fluid flow, complex phase diagrams, and magnetic properties provides extremely adaptable support and builds core competencies for many division and laboratory programs. For example, the expertise in phase diagram prediction for multicomponent alloys has proved applicable to casting and soldering programs alike.

Several excellent Metallurgy Division projects contribute to the laboratory's programs on Metal Processing and support the NIST Consortium on Casting of Aerospace Alloys, the link between NIST and leading companies in the aeropropulsion industry. Phase diagram modeling is used to predict solidification paths for industrial alloys with 10 or more components, information critical to simulations to determine soundness of castings. This application of modern computational tools is world class and provides new design capabilities for the development of industrial superalloys. In collaboration with industrial partners, a software package incorporating these results is being used to reduce the process development time and cost of investment castings used in high-performance aircraft and industrial gas turbines.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

Another example of how expertise in fundamental modeling techniques supports research in a technologically important area is the use of phase diagram prediction techniques to select potential lead-free alloys for soldering evaluation by industrial partners. In general, the projects related to development of lead-free, high-temperature solders and soldering technology are well designed and provide fundamental knowledge relevant to future technology development.

The panel considers the work being done by the Magnetic Materials Group on giant magnetoresistance (GMR) materials to be in a class by itself. In 1996, innovative discoveries such as the use of oxygen as a surfactant in the growth of GMR materials allowed this group to achieve the largest GMR value ever recorded. The outstanding quality of planning and research, together with the assembly of world-class equipment for preparing and characterizing GMR materials, has fostered the support and collaboration of leading industrial and academic organizations on commercialization of this technology.

Although the efforts in hardness standardization may not be as glamorous as other NIST programs, they are pertinent and greatly benefit U.S. industry. Continued improvement in product quality will require detailed international standards, such as those developed for the International Organization for Standardization (ISO). The division's efforts to reduce uncertainties in primary standard hardness materials through better understanding of test requirements are therefore timely and well directed. The microhardness standardization efforts are detailed and have the precision necessary to calibrate standards and to assess the effect of parameters on measurement accuracy. The panel was impressed with this project, although it was unclear why more stress was not placed on the microhardness aspect of this standards program.

The Electrochemical Group has made significant progress in initiating programs over the past 2 years. New activities include contractual work for the American Dental Association on development of replacements for mercury-containing amalgams and a project using nontoxic trivalent electrolytes in place of toxic hexavalent electrolytes to deposit chromium in commercial electroplating processes. The group has also made good progress in reducing uncertainties in primary and secondary coating thickness reference standards. As the work on chromium and copper electroplating technology and other new programs develop, the current array of industrial collaborators will not be enough to facilitate future commercial implementations. It is important to avoid duplicating industrial research efforts on critical life-cycle and environmental issues and to ensure that NIST programs are focused on specific industrial concerns.

Industrial Impact

A number of this division's programs clearly demonstrate the benefits of cooperation between industry and national laboratories, and the groups use these collaborations as effective technology transfer mechanisms. The projects on lead-free solders, the GMR effect, grain defects in single-crystal aerospace components, and phase diagram and solidification path analysis are all examples of successful industrial interactions. As mentioned earlier, many of the leading companies in the electronics, automotive, jet engine, and dental materials industries depend on the core competencies established within the Metallurgy Division.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×
Resources

Funding sources for the Metallurgy Division (in millions of dollars):

 

Fiscal Year 1996

Fiscal Year 1997 (estimated)

NIST-STRS

7.6

7.8

ATP

0.7

0.8

OA/Reimbursable

2.3

2.5

Total

10.6

11.1

The staff of the Metallurgy Division includes 55 FTP positions, 50 of whom are technical professionals. There are 11 non-FTP/supplemental personnel, including full-time temporaries, postdoctoral students, faculty, and other part-time workers.

Shrinking budgets and an aging workforce will pose major challenges to the division's efforts to maintain the high-quality programs currently under way. In some areas, these issues are already affecting the quality of work at NIST.

The Metal Data and Characterization Program's development of methodology and equipment to characterize high-temperature properties of superalloys produces accurate thermophysical properties of solid and liquid metals not available elsewhere. This program is a national resource. However, the effort is hampered by lack of space and the absence of instruments needed for state-of-the-art capability. Not enough data can currently be collected to create the database needed to have a broad impact on future alloy development.

The staffing and facilities of the superalloys high-temperature measurement group have dropped below the critical level necessary for world-class impact. The low level of resources available to this group prevent it from providing industry with timely data on a broad range of superalloys and titanium alloys and a wide range of their properties.

Finally, this division has several programs supporting NIST's Advanced Technology Program (ATP) focus areas in metal forming and powder consolidation. This work capitalizes on NIST's unique access to experimental resources. However, parts of the programs require laboratory equipment that is available at NIST but has not been used much in recent years. Such instruments need to be replaced in order to develop world-class competency in these areas. The panel cautions that in efforts to support ATP projects, this sort of problem may occur repeatedly.

Planning

There are three general comments from the panel on planning at the divisional and laboratory levels. First, the project summaries in the annual technical activities reports contain descriptions of deliverables and accomplishments similar to those listed in previous years. There seldom are figures or tables highlighting significant new accomplishments that clarify the time frame in which various accomplishments were achieved and make the report more interesting and understandable. To some extent, these technical activities reports could serve as marketing tools for NIST capabilities. Second, the panel wants to emphasize the importance of planning for

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

staff development in the current environment of flat or declining real budgets. Although the division does appear to work at building core competencies through hiring and training, division and laboratory management have not formalized a plan to maintain and improve the expertise of divisional personnel, perhaps through official programs for continuing education. Finally, there is no formalized procedure to ensure that the best proposals are selected for funding. It is unclear if stronger management oversight can improve project selection without creating an administrative burden and reducing staff creativity.

Two specific planning areas were of particular concern to the panel. In the selection and planning for ATP support programs, as discussed previously, it is unclear how the division will provide resources for necessary equipment upgrades and personnel training. In addition, the panel is concerned about the design of a more thorough plan for the next phase of the powder atomization and spray deposition project. The development of powder atomization sensors for process controllers is complete, but the focus of the proposed spray coating programs does not include work on life-cycle and green manufacturing concerns. Workshops and industrial collaborations have not yet clearly identified areas in which this group can achieve maximum technological impact. New equipment will probably be required to support development of a science-based competence focused on industrial needs.

MAJOR OBSERVATIONS

  • The technical merit of the Materials Science and Engineering programs was generally excellent, and the goals of the projects viewed by the panel were consistent with the laboratory's mission and called on the unique strengths of the laboratory staff.

  • The panel applauds the laboratory's continued focus on standards and is pleased to see new measurement technologies produce new SRMs. However, the laboratory's current level of involvement in the international arena is insufficient to accommodate the growing importance of global standards to U.S. industrial competitiveness.

  • The Materials Science and Engineering Laboratory has made good progress in planning but does not always define expected deliverables for each program. Such planning can be important in attracting industry participation and can facilitate preparation of application notes as the program proceeds.

  • The panel recognizes that the laboratory has begun to explore the use of the Internet for effective distribution of information about programs and results. However, it was generally unclear whether there is an optimal approach to dissemination through the World Wide Web and whether the Materials Science and Engineering Laboratory and NIST can serve as models of effective Internet use.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×
Reactor Radiation Division

This annual assessment of the activities of the Reactor Radiation Division of the Materials Science and Engineering Laboratory is based on a meeting of the Subpanel for Reactor Radiation at the National Institute of Standards and Technology on March 12–13, 1997, and on the document NIST REACTOR: Summary of Activities October 1995 through September 1996.2

Members of the subpanel included David L. Price, Argonne National Laboratory, Chair; Alice P. Gast, Stanford University; Walter Kohn, University of California at Santa Barbara; Theodore R. Schmidt, Sandia National Laboratories; and Gen Shirane, Brookhaven National Laboratory.

Mission

The Reactor Radiation Division stated its mission as: (1) to operate the NIST research reactor in a safe, cost-effective manner in order to meet critical national needs while protecting the safety of the general public and NIST staff; (2) to develop and use powerful measurement methods based on the NIST Research Reactor to conduct a diverse, world-class program of basic and applied research relevant to NIST mission goals in the broad areas of materials science and engineering, physics, chemistry, and biological science; and (3) to manage the facilities of the NIST research reactor, including the Cold Neutron Research Facility (CNRF), as a major national resource to serve the needs of NIST, industry, universities, and other government agencies.

The division's activities are central to NIST's mission to promote U.S. economic growth by working with industry to develop and apply technology, measurements, and standards. The NIST Research Reactor is a unique and outstanding facility for neutron research that provides diverse capabilities for the national and international scientific communities and the opportunity for high-quality research by the Reactor Radiation Division staff and their collaborators. More than 95 percent of the work done at the reactor is in the form of joint projects involving organizations within NIST, other government agencies, industrial laboratories, and universities. Collaborative projects within NIST include extensive work with the Materials Science and Engineering Laboratory in the areas of ceramic coatings, magnetic nanoparticles, residual stress analysis, and polymer blends; with the Chemical Science and Technology Laboratory in the areas of biological structure and dynamics, complex fluids, and neutron beam activation analysis; and with the Physics Laboratory in the areas of magnetic thin films, neutron physics, standards, and dosimetry. The Chemical Science and Technology Laboratory and the Physics Laboratory also run several experimental stations at the reactor. There are less extensive but significant collaborations with the Electronics and Electrical Engineering Laboratory, the Building and Fire Research Laboratory, and the Advanced Technology Program. The Reactor Radiation Division is also linked to NIST Technology Services through the Crystal and Electron Diffraction Data Center.

2  

U.S. Department of Commerce, Technology Adminitration, National Institute of Standards and Technology, NISTIR 6000, National Institute of Standards and Technology, Gaithersburg, Md., 1997.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×
Technical Merit and Appropriateness of Work

The NIST Research Reactor, with its associated instrumentation and scientific and technical staff, is a world-class resource for the national and international research communities.3 It is the only major American research reactor currently operating with a cold neutron source, and its instrumentation for cold neutron research is in many ways unique within the United States. At least one piece of equipment, the new reflectometer, is the best instrument of its kind in the world. The NIST reactor's importance to the national scientific scene is enhanced by the cancellation of the Advanced Neutron Source project and the recent shutdown and potential cancellation of the upgrade of the High Flux Beam Reactor at Brookhaven National Laboratory.

Instrumentation. The NIST research reactor incorporates an impressive list of neutron scattering facilities. Four-fifths of the instrumentation upgrades planned for the guide hall have been completed. A conspicuous success is the vertical reflectometer, which was recently moved from the confinement building to the guide hall. Last year's reactor upgrade, which installed a new H2 cold neutron source and increased the neutron flux by a factor of 6, further enhanced the power of this reflectometer. It can measure minimum reflectivities approaching 5*10−8 and is perhaps the world's best reflectometer. This instrument is currently being used for a series7 of important studies on polymers, membranes, and other multilayers.

Another major achievement is the recently completed cold neutron triple-axis spectrometer with polarized beam capability. This instrument, known as SPINS (for Spin-Polarized Inelastic Neutron Scattering), provides incident energies ranging from 17 to 2.0 meV and allows measurements of inelastic scattering with very low background. This triple-axis spectrometer and one of the two 30-meter small-angle neutron scattering (SANS) instruments make up the Center for High Resolution Neutron Scattering (CHRNS), jointly sponsored by the National Science Foundation (NSF) and NIST. Both the SPINS and SANS instruments are functioning according to their performance goals, and vigorous user communities have already developed to take advantage of these new tools. The second summer school on SANS and Reflectivity was held in June 1996 and was highly successful. In addition, a workshop on High Resolution Cold Neutron Spectroscopy was organized for August 1997.

The subpanel noted that improvements in the thermal neutron facilities in the reactor hall had begun but were not yet complete. An exciting new spectrometer for residual stress measurement was recently installed, and this instrument is now providing useful data with direct industrial applications. A new powder diffraction spectrometer with a choice of three monochromator crystals is also essentially finished. However, the three triple-axis spectrometers in the reactor hall still urgently need upgrading. For a relatively small capital cost, these can be transformed into first-rate instruments whose capabilities will complement the spectrometers in the guide hall.

Research Projects. The division's Magnetism and Superconductivity Group conducts solid, high-quality work in areas of current interest. They have made extensive measurements on the magnetic and structural properties of the GMR crystal La(Sr)MnO 3. They have also observed interesting coherent scattering from epitaxial Fe3O4/CoO multilayers.

3  

Twenty to 25 percent of the users come from overseas.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

The groups investigating microstructures and interfaces are taking advantage of NIST's cold neutron reflectometry—a capability that, in the judgment of the subpanel, is the best in the world. The instrumentation at the reactor allows high-resolution studies of layer structures and interfaces (planar averaged) with a resolution of several angstroms. This capability is important both for basic scientific research and in technological and medical applications and will continue to grow in significance.

One research project presented to the subpanel involves diffusion of proteins through cell membranes, a basic biological process that is still not completely understood. A team of scientists from the Reactor Radiation Division and the Biotechnology Division of the Chemical Science and Technology Laboratory has performed successful studies on a model system in which the protein melittin is shown to have partially penetrated a hybrid bilayer membrane. The small change in the layer-averaged scattering length density that results from this partial penetration can be detected only through the high sensitivity of the NIST reflectometer.

Another project under way involves structures with alternating magnetic and nonmagnetic metallic layers. Because the electrical resistance of such structures is extremely sensitive to externally applied magnetic fields (GMR), these layered compounds are highly attractive candidates for magnetic readout devices. The general mechanism is understood and depends on the magnetic coupling of successive magnetic layers. This coupling can be ferromagnetic or antiferromagnetic, depending on the thickness of the intercalated metallic layer. Using the NIST polarized neutron reflectometer, studies of such structures are investigating complex variations in spin-spin correlations within a single magnetic plane and between two successive magnetic planes as functions of interplane spacing, applied magnetic field, and temperature. The results suggest complex ferro/antiferromagnetic patterns that are not yet uniquely determined. The data's precision is absolutely essential and represents a strikingly successful demonstration of NIST's unique capabilities in polarized neutron reflectometry.

The Chemical Physics of Materials Group is investigating the structure and dynamics of a variety of systems of scientific and technological interest, including catalysts, optical materials, polymers, and biological systems. This group has recently established an international reputation through its work on the orientational dynamics of C60 and fullerenes. This approach is now being extended to cubane (C 8H8), a remarkable molecule that is an atomic-scale replica of a cube. Another new activity is the project on rare-earth hydrides, which have recently been found to have unique optical switching properties. This work is a good use of the group's extensive experience in metal-hydrogen systems.

The macromolecular and microstructures studies of the division are centered on the use of three Small Angle Neutron Scattering (SANS) instruments, two of which are 30-m high-resolution instruments and one of which is 8 m. The projects in this field involve collaborations with a large and diverse user community. Although many of the experiments are part of the formal user program (the CHRNS SANS machine is totally dedicated to this program), division scientists maintain active research programs in the areas of complex fluids and colloidal mixtures as well as some areas of polymer science. Among the highlights of this work are studies of supercritical carbon dioxide–based microemulsions, shear-induced structural transitions in polymer micelle solutions, and pressure dependence studies of polymer blends.

The major research efforts of the crystallography team involve the use of the 32-detector high-resolution neutron powder diffractometer. Over the past year researchers have collected

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

more than 1,000 data sets on at least 330 different materials, many with direct relevance to industrial research and development needs. Accomplishments include determination of oxygen stoichiometry in the colossal magneto-resistance compound T12Mn2O7determined by Rietveld analysis of neutron powder diffraction data, precise analysis of the ratio of the tetragonal/cubic phases of the zirconia feedstock for sprayed ceramic thermal barriers, and development and characterization of a new zeolite SRM. In addition to the powder diffraction work, the crystallography team has launched a major program to study residual stress in bulk materials using the newly developed diffractometer on beam tube 8.

The Reactor Radiation Division assumed responsibility for the NIST crystal database 15 years ago. The 1995 subpanel recognized the importance of this resource and its appropriateness in the context of NIST' s general mission but believed that the database was not used enough. That subpanel was concerned about the marketing strategy for this database and whether there was enough customer input. Since that 1995 assessment, NIST has developed a plan for this database incorporating three elements:

  • To focus the database on metals and inorganic chemicals, areas consistent with the current scientific emphases within the Reactor Radiation Division;

  • To establish a redirected Crystal and Electron Diffraction Data Center involving both the Reactor Radiation Division and NIST Technology Services; and

  • To plan for a future database including the inorganic chemical properties data already available at NIST, and to pool information and software with an inorganic database in Germany and a metallurgical database in Canada.

A new commercial product developed from these plans should be available in about 2 years. The subpanel is strongly encouraged by this plan and by NIST management's apparent support for it.

Reactor Operations and Engineering. Although the reactor was shut down between May 1994 and September 1995, several different upgrade and maintenance projects were completed. The reactor main heat exchangers were replaced, and an extra exchanger was piped in as a spare. This repair allowed the reactor to return to its designed power level of 20 MW. Several lesser heat exchangers were also replaced. The top refueling plug of the reactor was completely refurbished and the inventory of heavy water replaced to reduce tritium levels. A complete visual inspection of all in-core components was completed. Reactor instrumentation was upgraded in several areas. The neutron guides within the confinement building were encased in steel vacuum vessels to remove stresses coming from unbalanced pressures. The remaining three guides were installed, bringing the total to seven. The liquid hydrogen cold source was installed and commissioned, and a new instrument for measurement of residual stress was installed.

The operation of the reactor and the new cold source over the past year has been remarkable because of the latter's high availability during this first year after the installation. The reactor has been in operation at 20 MW for 70 percent of real time, and the cold source has had greater than 99 percent reliability. For several years before the upgrade, the reactor was limited to operation at 15 MW, so this year's operation is a return to the licensed power levels. In addition, the reactor was in operation 100 percent of the scheduled time. From the results of this first postinstallation year, it is clear that the staff and engineers who designed, fabricated,

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×

installed, and tested all of the hardware and components during the extended outage did outstanding work. Fundamental performance indicators such as high reactor availability, low inadvertent scrams, and minimal off-normal events were all highly satisfactory during this period.

The report of the Safety Audit Committee (SAC), various training records, documentation of emergency drills and exercises, and levels of personnel radiation exposure were all examined by the subpanel. The most recent SAC review focused on maintenance activities, and the reactor staff are responding to the reported need to update maintenance procedures. Training records for reactor operators were spot checked and deemed adequate. The most recent emergency exercise and drill were reviewed and the follow-up was adequate. Given the potential for exposure, personnel radiation exposures during the upgrade of the reactor coolant system and refurbishing of the reactor head were extremely low. The total exposure was about 11 man-rem with all individuals receiving less than 1 rem each. (The normal occupation external radiation exposure limit is 5 rem, so all workers received less than 20 percent of the maximum allowable.) Significant improvements have been made in the guide hall to minimize personnel radiation exposure by enhancing shielding, providing controlled enclosures, and improving administrative practices. The Health Physics and Engineering staffs are to be commended for their active commitment to controlling radiation exposure of personnel.

In late 1995, the Nuclear Regulatory Commission conducted a comprehensive inspection of the reactor facility to assess the division's readiness to resume full power operation after the upgrades. The inspection determined that the reactor programs reviewed “consistently exceed regulatory requirements.”

The condition of the physical plant was reviewed and found to be excellent. Evidence of the recent major upgrade in 1994–95 as well as of numerous other ongoing improvements in the reactor systems and infrastructure were clearly observed. The staff are aggressively modernizing systems to avoid the problems normally associated with a 30-year-old facility and its equipment. Furthermore, the engineering staff have identified a series of improvements in the geometry of the cold source that could double the cold neutron output. These upgrades in the source will provide a significant enhancement to neutron scattering capabilities.

The staff are also working on several other issues of concern, including the shipment of spent fuel to the Savannah River Site, the fabrication of new spent fuel storage racks, and the maintenance of the spent fuel storage pool.

Industrial Impact

The subpanel was impressed by the level of industrial involvement at the reactor and guide hall. Industrial partners such as Exxon, Texaco, and IBM are members of Participating Research Teams for specific instruments. In addition, company researchers are active members of the reactor's user community. For example, about 15 percent of the 66 proposals for use of the High-Resolution Powder Diffractometer from July 1996 to February 1997 were industry based, including three proprietary projects.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
×
Resources

Funding sources for the Reactor Radiation Division (in millions of dollars)4:

 

Fiscal Year 1996

Fiscal Year 1997 (estimated)

NIST-STRS

12.8

13.4

ATP

0.3

0.2

OA/Reimbursable

1.9

1.8

Total

15.0

15.4

The staff of the Reactor Radiation Division includes 78 full-time permanent (FTP) positions, 73 of whom are technical professionals. There are 15 non-FTP/supplemental personnel, such as full-time temporaries, postdoctoral students, faculty, and other part-time workers.

The base budget for the reactor has been stable for some time, augmented by internal NIST funding as required for major upgrades as well as activities associated with the current relicensing project. NIST upper management has recognized that nuclear facilities must have adequate resources to provide the requisite level of safety and compliance; as a consequence, they have maintained the reactor's budget appropriately. One potential area of concern is the recent turnover at all levels of NIST management, including the Materials Science and Engineering Laboratory director and the director of NIST. In the past, management support of this facility has enabled it to operate as a world-class facility. The steady funding of the budget has contributed to the stability among the management and staff of the Reactor Radiation Division. This consistency is a prime asset in ensuring the facility 's safe operation.

OA support represents about 9 percent of the total division budget of $21 million (including capital equipment funds). The largest single item in this support is $1.3 million from the NSF to support the CHRNS. Because the national scientific user community has access to most of the beam time on the two instruments that make up the CHRNS (75 percent of the available time on the SANS and 67 percent on the spectrometer), as well as 25 to 67 percent of the available time at eight other facilities at the CNRF, the NSF is clearly receiving a high return on its investment.

About 700 scientists visit the reactor each year to conduct experiments under the user programs, through which researchers from the United States and overseas can apply for time on the neutron facilities. The time available to outside researchers on each set of instruments depends on how those instruments are funded; if a company has sponsored the equipment on a given beam line, then a certain percentage of the operating time on those instruments is set aside for that company. The time for outside users is then allocated on a competitive basis. Final decisions are made by the Program Advisory Committee, a group of seven prominent scientists appointed by NIST management from the national users' community. This process works very well, and the subpanel found an exceptionally high degree of user satisfaction.

4  

The totals for the reactor include only normal operation costs. Fuel cycle and upgrade costs, totaling approximately $5 million per year, are excluded.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
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The funding and personnel resources listed above appear to be generally adequate for the division to meet its stated objectives and explore further opportunities as they arise. However, there are some personnel issues that require hiring both new and replacement personnel for whom funding and slots are not currently allocated.

Over approximately 30 years of operation, the NIST reactor has become a truly exemplary facility that plays an indispensable role today in U.S. neutron science. An essential element in this history has been the outstanding and harmonious administration of the division over several decades by the administrative chief, the chief of reactor operations and engineering, and the leader of the Condensed Matter Science Group. These three staff members range in age from 58 to 65. Preparing for their replacement as they retire within the next decade is of paramount importance to the division's future. The current leadership is fully aware of this and has made short-term plans in the event that one of them becomes unavailable. There has also been some progress in preparing younger members of the division for broader leadership roles. Given the complex regulatory environment of the reactor, some overlap between current and future leadership is important in management training. Currently there are not many formal systems in place to prepare younger staff in this way. At universities, management experience is occasionally gained through participation in administrative councils or through rotation into a position of authority, such as department chair.

Most of the senior staff in Reactor Operations and Engineering will become eligible for retirement within the next 3 years, and problems could arise unless division management anticipates personnel replacement needs and hires appropriately. The 1995 subpanel also emphasized these potential personnel requirements. Although division management has made a serious effort in this direction, it is clearly proving difficult to identify appropriate candidates. This issue remains a major concern of the subpanel and an essential goal of the division.

The 1995 subpanel also noted that the Reactor Radiation Division did not have enough theorists. Two scientists from other institutions have since become active in theoretical efforts at the reactor. Although their involvement is a positive step, these individuals are focused more on modeling than on fundamental condensed matter theory, which still concerns the subpanel. One staff theorist retired after the 1995 assessment, so the subpanel now believes that the division lacks the expertise that would be provided by two new staff theorists.

Planning

The division's strategy consists of four points: (1) continual upgrade of all facilities: upgrade thermal neutron instruments; prepare for reactor relicensing; (2) improved outreach, better customer service: continually seek new interaction mechanisms; develop new methods and applications of neutron techniques; (3) maintaining scientific leadership: target specific areas of research (e.g., reflectivity); strong collaborative ties with best groups worldwide; (4) proactive safety and regulatory position: absolute commitment to safety and as low as reasonably achievable (ALARA) levels of radiation exposure; ongoing dialogue with regulatory agencies.

The strategy outlined above seems appropriate. The planning process was also discussed with a representative of the CNRF Researchers Group, who expressed great satisfaction with the

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
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process of community involvement and with the Reactor Radiation Division 's responsiveness to issues raised by the group.

The Strategic Plan for the Materials Science and Engineering Laboratory (June 1996) includes the transition of the NIST research reactor from a division of the laboratory to a national Center for Neutron Research. This change has already been accepted by NIST management and occurred officially on May 25, 1997. The subpanel enthusiastically endorses the proposed change. The designation as a Center will give the reactor facility status and exposure more appropriate to its national and international importance. It will also provide the director of the facility with a level of authority more commensurate with his responsibilities.

The present reactor license will expire in 2004. The Reactor Operations Group is preparing a Safety Analysis Report (SAR) and an application for relicensing through 2024. The SAR is currently in draft form and will be reviewed by the staff and the Safety Evaluation Committee over the next year. A factor in timely relicensing is the healthy ongoing dialogue maintained between the NIST Reactor staff and the Nuclear Regulatory Commission. The Reactor Operations Group is aware of the critical milestones and time constraints, but there is no short planning document that identifies and summarizes the key issues. In view of the NIST reactor's unique role in the nation's neutron science capabilities for the foreseeable future, it is essential that this relicensing take place. The subpanel strongly endorses the need for timely relicensing to ensure continuity of service to users. The physical condition of the reactor and associated plant and facilities should present no serious obstacles.

Major Observations

  • The reactor upgrade has been completed and was very successful. The newly installed H2 cold neutron source increased the neutron flux by a factor of 6. The reactor has returned to the licensed level of 20 MW and has operated reliably since it was restarted.

  • The panel recognizes and supports the division's emphasis on planning for the orderly replacement of the three key members of the Reactor Radiation Division leadership over the next decade.

  • Efforts to hire appropriate staff for Reactor Operations and Engineering are continuing but have not yet been completely successful.

  • The panel is concerned about the loss of expertise in fundamental condensed matter theory within the division since the last assessment.

  • The cold neutron instrumentation upgrade is nearing completion. The focus is appropriately shifting to upgrading the thermal neutron facilities in the reactor hall, including the three triple-axis spectrometers.

  • The new strategy for the NIST crystal and inorganic chemical properties database appears appropriate.

Suggested Citation:"6 Materials Science and Engineering Laboratory." National Research Council. 1997. An Assessment of the National Institute of Standards and Technology Programs: Fiscal Year 1997. Washington, DC: The National Academies Press. doi: 10.17226/9208.
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