E
Government Programs in Corrosion
Before describing individual government programs in corrosion it is worthwhile to reiterate that mitigation of materials degradation need not be done in isolation even though government departments have differing needs. One way the committee believe the current “go-it-alone” approach can begin to be alleviated is for the Office of Science and Technology Policy (OSTP) to launch a concerted, multiagency effort to support high-risk, high-reward research designed to develop technologies that mitigate the societal impact of corrosion. OSTP could, for example, as recommended by the committee in Chapter 5 of this report, constitute a multiagency committee on environmental degradation of materials with the responsibilities of documenting the current federal expenditures on corrosion research and mitigation and encouraging multiagency attention to issues of research, mitigation, and dissemination of information. Collaboration among departments and agencies could be augmented by collaboration with state government and private entities such as professional societies, industry consortia, and standards-making bodies.
THE DEPARTMENT OF HEALTH AND HUMAN SERVICES AND THE FOOD AND DRUG ADMINISTRATION
The Department of Health and Human Services (HHS) is the federal government’s principal agency for protecting the health of all Americans and providing
essential human services, especially for those who are least able to help themselves.1 Within HHS, the Food and Drug Administration (FDA) is the agency that is most concerned about corrosion. The FDA is responsible for protecting public health by ensuring the safety, efficacy, and security of human and veterinary drugs, biological products (including blood, vaccines, and tissues for transplantation), medical devices, the nation’s food supply, cosmetics, and products that emit radiation. The FDA regulates $1 trillion worth of products a year2 and also enforces Section 361 of the Public Health Service Act and associated regulations, including sanitation requirements. Its interest in corrosion concerns issues such as maintaining antiseptic conditions for the manufacture and packaging drugs and for the handling and processing of food products; understanding corrosion products that can leach into the body from materials such as dental amalgams and implanted medical devices; and ensuring the safety of medical equipment such as tanks that hold and dispense medical gases. The FDA issues good guidance practices that set forth statutory and regulatory requirements, such as testing methods to be used to demonstrate capability, that relate to corrosion testing standards.
For example, the FDA addresses concerns about corrosion of implantable medical devices3 through requirements for biocompatibility (i.e., a device’s effect on the body) and biostability (i.e., the body’s effect on a device). Implantable medical devices are becoming increasingly important, given that they can replace a failing heart valve, correct an irregular heart rhythm, replace a worn out hip or knee joint, save a patient from ischemia-induced fibrillation, or even stop the tremors associated with Parkinson’s disease. Companies attempting to secure approval to sell implantable devices must demonstrate both biocompatibility and biostability. Biocompatibility is usually demonstrated by passing standardized tests that meet the guidelines set forth in ISO 10993-Part 1. Materials that corrode probably will not pass these tests because they will cause an inflammatory response or a sensitization reaction. Corrosion is also a major concern for ensuring biostability, which can be assessed in standard laboratory corrosion tests or in vivo from actual experience with implant. Typically, a manufacturer selects a specific type of test and information to submit to the FDA to demonstrate stability of a device in the body; the FDA reviews the data and may approve the submission or require additional data. It is because of these FDA requirements that implantable devices today are made from noncorrosive materials,4 and corrosion is not currently a significant issue.
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See http://www.fda.gov/RegulatoryInformation/Legislation/default.htm. |
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These devices are implanted in the body for long periods of time, sometimes a decade or more. |
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Materials such as platinum, titanium, silicon rubber, some fluropolymers, and various polyurethanes are among the mainstays in this industry, along with a few exotic nickel-based superalloys. The most “common” material found in implantable medical devices is likely 316 stainless steel. Other than improved wear resistance, there is little driving force for advancing materials in this application. |
DEPARTMENT OF COMMERCE AND NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY
The National Institute of Standards and Technology (NIST) has responsibility within the Department of Commerce for the technical areas related to corrosion. Corrosion research at NIST (formerly the National Bureau of Standards) laboratories dates back to 1911, and initially focused largely on aqueous corrosion of metals, and corrosion under coatings such as exterior paint. In the last of the studies on metals, conducted in the 1970s, fundamental work on stress-corrosion cracking helped to elucidate and quantify the combined effects of chemistry and mechanical stress on alloy degradation. Current corrosion research at NIST is centered in the Building and Fire Research Laboratory and includes a self-contained, accelerated testing facility (SPHERE) that enables realistic environments and simultaneous measurements of multiple variables.
DEPARTMENT OF DEFENSE
The Department of Defense (DOD), with supporting legislation, has introduced a comprehensive program aimed at preventing and mitigating corrosion of military equipment and facilities. The director of the DoD Corrosion Policy and Oversight Office leads the DOD development of an overarching long-term strategy across all the military services. The program emphasizes corrosion prevention and mitigation, incorporates uniform testing and certification of new technologies, facilitates the interchange of corrosion information, and establishes a coordinated R&D program with specific transition plans. The primary objective is reducing the effects of corrosion on the safety and readiness of the American warfighter, as well as lowering the cost of corrosion to the American taxpayer.5 The R&D program priorities have been guided by field problems. It is estimated that corrosion accounts for 15 to 30 percent of the cost of maintaining military equipment, such as ships and ground vehicles. The top 10 corrosion drivers for each type of equipment are aggressively addressed through mitigation efforts. The effort has produced measurable results: over a 5-year period, 342 projects were submitted for funding, and 141 were selected based on calculated return on investment. The typical project
lasted 2 years, followed by implementation. The DOD estimates that the return on investment for the $138 million spent was greater than 50:1, since the life-cycle corrosion avoidance cost was calculated to be $5.75 billion.6
A set of Army, Navy, and Air Force laboratories in the federal laboratory system have historically addressed corrosion issues for DOD. For instance, U.S. Navy laboratories have supported corrosion research in seawater and/or marine atmospheres for many years. The lead laboratory with responsibility in corrosion science is the Naval Research Laboratory (NRL), which has conducted corrosion research for many years in the Corrosion Science and Engineering Branch. This branch is funded by the Office of Naval Research, sea systems commands, and specific project offices. Work in the 1950s and 1960s was some of the first to embrace fracture mechanics, developed by Irwin and others as a modern way to understand stress corrosion cracking and advance the concept of defect tolerance in the case of stress corrosion cracks and threshold stress intensity factors. Later, work on stress corrosion cracking of emerging titanium alloys was advanced at NRL on behalf of other agencies such as NASA. Work continues today at the NRL-Corrosion Division that includes topics ranging from environmental fracture to passivity. However, research is also conducted at various other Navy laboratories that are focused on subsets of naval equipment and infrastructure. These labs are now organized as a part of NAVSEA and/or NAVAIR warfare centers.7 All of these labs have a specific mission, and corrosion topics as such are very applied and often funded from project offices and platform programs.8 When a persistent fleet problem suggests that testing and evaluation be conducted, these NAVSEA/NAVAIR warfare labs could conduct the research. NRL could address generic science questions. The Army and Air Force fund basic research through the Army Research Office and the Air Force Office of Scientific Research, plus laboratories within the development and operational commands. But the corrosion R&D in these services is typically less comprehensive than that in the Navy, and corrosion research is a small portion of the portfolio for both internal and external work.
DEPARTMENT OF ENERGY
The overarching mission of the U.S. Department of Energy (DOE) is to advance the national, economic, and energy security of the United States.9 DOE funds R&D at its national laboratories, smaller federal institutes, universities, private research companies, and industry, in a wide range of technical areas. Most of this funding is awarded competitively and seeks to address key fundamental and technical issues impacting national and energy security. DOE’s R&D portfolio encompasses pure discovery science, use-inspired basic studies, applied research, and technology maturation and deployment, with different offices devoted to different parts of this spectrum of activities. Fundamental research in corrosion science is funded primarily though the Office of Science. Most corrosion R&D under DOE’s auspices has been in support of specific technologies, whether generically or to attack a specific targeted problem or goal, and is distributed throughout DOE’s multiple technology offices. A few examples include the following:
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Office of Fossil Energy: Efforts to qualify and improve corrosion resistance of materials needed for advanced supercritical reactors or combined-cycle gasification.
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Energy Efficiency–Distributed Energy, Fossil Energy: Development of oxidation-resistant ceramic composites and bond coats for gas turbines.
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Energy Efficiency–Industrial Technologies: Development of corrosion-resistant alloys and refractories for materials and chemical processing.
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Nuclear Energy: Improved understanding of degradation modes and prediction of lifetimes for materials for long-term storage of spent nuclear fuels
Looking toward to the future in terms of technological driving forces and the scientific capabilities currently available or just emerging, DOE conducted two recent workshops that included consideration of basic research needs involving corrosion in relation to advanced nuclear energy and the behavior of materials in extreme environments.10,11
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Department of Energy, Basic Research Needs for Advanced Nuclear Energy Systems, Report of the Basic Research Needs for Advanced Nuclear Energy Systems Workshop, July 31-August 3, 2006, available at http://www.sc.doe.gov/bes/reports/abstracts.html#ANES. |
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Department of Energy, Basic Research Needs for Materials under Extreme Environments, Report of the Basic Energy Sciences Workshop on Materials Under Extreme Environments, June 11-13, 2007, available at http://www.sc.doe.gov/bes/reports/files/MUEE_rpt.pdf. |
DEPARTMENT OF TRANSPORTATION
The Department of Transportation (DOT) was established by an act of Congress on October 15, 1966, with the mission to serve “the United States by ensuring a fast, safe, efficient, accessible, and convenient transportation system that meets our vital national interests and enhances the quality of life of the American people, today and into the future.”12 The DOT comprises 10 operating administrations:
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Federal Aviation Administration (FAA),
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Federal Highway Administration (FHWA),
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Federal Motor Carrier Safety Administration (FMCSA),
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Federal Railroad Administration (FRA),
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Federal Transit Administration (FTA),
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Maritime Administration (MA),
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National Highway Traffic Safety Administration (NHTSA),
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Saint Lawrence Seaway Development Corporation (SLSDC),
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Pipeline and Hazardous Materials Safety Administration (PHMSA), and
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Research and Innovative Technology Administration (RITA).
Each of the 10 operating administrations has some degree of involvement with corrosion—either through research (e.g., FAA, FHWA, PHMSA) or asset renewal (e.g., SLSDC). Most operating administrations provide guidance and in some cases requirements for mitigating and controlling corrosion. In addition, several operating administrations fund research in corrosion science and engineering. For example, the PHMSA sponsors research on regulatory and enforcement activities and on developing the technical and analytical foundation necessary for planning, evaluating, and implementing the pipeline safety program. The research and development projects focus mainly on providing near-term solutions to increase the safety, cleanliness, and reliability of the nation’s pipeline system, including corrosion issues.13 The RITA takes a different approach and funds university transportation centers (UTCs) that perform research on a broad range of research topics. Some topics researched under the UTCs include corrosion issues. In addition, the Office of Infrastructure Research and Development funds transportation infrastructure research, including research on corrosion in the infrastructure. Past corrosion research has included assessing the corrosion performance of different types of concrete reinforcement, assessment of corrosion protection systems, and assessment of materials and methods for corrosion control.14
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
The National Aeronautics and Space Administration (NASA) began corrosion studies at the Kennedy Space Center (KSC) in 1966 during the Gemini/Apollo Programs with the evaluation of protective coatings. The Corrosion Technology Laboratory evolved from the need to better understand the corrosion processes affecting the KSC launch sites. Over the years, numerous material failures at KSC have been attributed to various forms of corrosion. To address these issues, basic and applied research is performed at the KSC Beachside Atmospheric Exposure Site to identify technologies that will prevent such failures. Research conducted for other NASA centers includes work at the Johnson Space Center in Houston, Texas; the Stennis Space Center in Hancock County, Mississippi; the Langley Research Center in Hampton, Virginia; and the Marshall Space Flight Center in Huntsville, Alabama. NASA also partners with universities to investigate corrosion. Two documents currently guiding NASA’s corrosion efforts are NASA-STD-5008A, Standard for Protective Coating of Carbon Steel, Stainless Steel, and Aluminum on Launch Structures, Facilities, and Ground Support Equipment,15 and TM-584C, Corrosion Control and Treatment Manual.16
NASA’s hot corrosion research at the Glenn Research Center dates back to late 1970s. NASA has conducted extensive research on understanding the thermodynamics and kinetics of sodium sulfate deposition in gas turbine engines. The research resulted in identification of conditions leading to deposition of sodium sulfate in turbine engines and correlating salt deposition rates to turbine operating conditions. In the early 1980s NASA’s hot-corrosion research focused on understanding hot corrosion of superalloys through laboratory and burner rig testing, as well as low-temperature hot-corrosion mechanisms of nickel-based alloys. NASA discontinued hot-corrosion research in 1985, but it is currently being revived to address issues related to corrosion of advanced turbine disk alloys.17 Activities include understanding corrosion mechanisms and developing coatings to mitigate corrosion without adversely impacting mechanical properties. NASA Glenn has also made substantial contributions to the understanding of the high-temperature oxidation and degradation of superalloys, aluminides, silicon-based ceramics and
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NASA, Standard for Protective Coating of Carbon Steel, Stainless Steel, and Aluminum on Launch Structures, Facilities, and Ground Support Equipment, NASA-STD-5008A, available at http://corrosion.ksc.nasa.gov/publications.htm. |
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NASA, Corrosion Control and Treatment Manual, TM-584C, available at http://corrosion.ksc.nasa.gov/publications.htm. |
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NASA GRC facilities to study hot corrosion include Mach 0.3 burner rigs and a high-pressure burner rig, a high-temperature mass spectrometer (one of the two in the country) to study chemistry of salt deposition, and a multitude of laboratory rigs, including microbalances, to study hot corrosion under controlled atmospheres. |
ceramic composites, and other very-high-temperature materials. Researchers there were at the forefront of the development of environmental barrier coatings as well as specific experimental techniques for high-temperature studies, including extensive characterization and modeling of oxidation of alumina-forming alloys under thermally cycling conditions.
NATIONAL SCIENCE FOUNDATION
As described in its strategic plan,18 the National Science Foundation (NSF) is the only federal agency with a mission that includes support for all fields of fundamental science and engineering,19 except for the medical sciences. In addition to funding research in the traditional academic areas, the agency also supports high-risk, high-payoff ideas and novel collaborations. NSF ensures that research is fully integrated with education, so that today’s revolutionary work will also be training tomorrow’s leading scientists and engineers.
A brief survey of current research grants funded by NSF showed that more than 40 dealt with various aspects of corrosion research. Topical focus ranges from traditional aqueous corrosion of metals to atmospheric degradation of nanostructures, and from science-oriented topics to engineering issues related to civil infrastructure. Research projects were found in divisions with responsibilities including materials, chemistry, and civil engineering and others. But there do not appear to be clear themes for the corrosion research projects and no apparent program strategy regarding corrosion research.
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National Science Foundation, Investing in America’s Future: Strategic Plan FY 2006-2011, NSF 06-48, September 2006, available at http://nsf.gov/publications/pub_summ.jsp?ods_key=nsf0648. |
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