Use of Lightweight Materials in 21st Century Army Trucks (2003)

The Committee on Lightweight Materials for 21st Century Army Trucks was asked to recommend research and development opportunities and programs aimed at evaluating and developing advanced materials, processes, and structural concepts for U.S. Army truck applications (see Chapter 2). In the process of identifying these opportunities, it became clear that a number of nontechnical issues had to be addressed in order to enable the insertion of lightweight structural materials and new processing technologies in Army truck applications (see Chapter 3).

The committee was also asked to recommend methods the U.S. Army Tank-automotive and Armaments Command (TACOM) can use to coordinate its advanced materials research efforts with industry and other federal agencies. This chapter presents the committee’s final conclusions and recommendations.

The committee’s conclusions regarding opportunities for materials research and development are summarized in Table 4-1. For the short and medium term, advanced galvanized steel alloys combined with selective, justified application of other advanced materials should meet most of the Army’s light-vehicle needs. A variety of steels in flat and plate forms are likely to remain the material of choice in the heavy-truck categories. Additionally, for the short term, a number of commercially available materials and technologies can be used for Army trucks, including high-strength and stainless steels, aluminum and magnesium alloys, and MMCs.

Manufacturing processes available today include superplastic forming, castings of aluminum and magnesium alloys, and the use of tailor welded stamping/forging blanks. For the medium term, materials such as dual-phase and ultrahigh carbon steels, aluminum 2519, magnesium, MMCs, and PMCs are candidates.

Finally, for long-term applications, Army trucks can benefit from investment in titanium, smart materials, and additive metal process technologies. Investments in advanced materials, including nonferrous alloys, composites, and coatings, that offer superior performance and reduced operations, maintenance, and service costs would serve the longer-term, mission-specific needs of future tactical trucks and combat programs. In such cases, the need for condition-based vehicle health monitoring cannot be overemphasized.

RECOMMENDATION. THE ARMY SHOULD PURSUE THE USE OF LIGHTWEIGHT STRUCTURAL MATERIALS IN ITS TRUCK FLEET, AS FOLLOWS:

• The Army should follow the guidance in the table "Summary of Opportunities for New Materials, Applications, and Research," in this report.

• Research programs should be funded to develop the technologies listed in the table as medium- and long-term opportunities, and these programs should include system integration, development testing, and field testing.

• The Army should support the development of databases of the properties of these materials as well as the development of models for processing lightweight materials and for predicting the performance of components manufactured using these materials.

The Army truck fleet continues to degrade faster than it can be upgraded through new acquisitions, forcing the Army to use recapitalization techniques simply to maintain the fleet size and effectiveness ratio.¹ While this approach permits the possible introduction of improved components such as the engine, it renders almost impossible advances in overall vehicle configuration and structural architecture or the introduction of new lightweight materials.

New brigade requirements such as enhanced mobility have created pressure to accelerate the introduction of lightweight materials into the truck fleet. In addition, an objective of the Revolution in Military Logistics (RML)

initiative is to reduce vehicle fuel consumption by 75 percent.² This initiative will most certainly require the aggressive application of lightweight materials.

Unfortunately, the application of lightweight materials may increase the acquisition cost of a new truck, even though the use of these materials may reduce life-cycle costs through enhanced corrosion resistance as well as reduced energy consumption. Although operations and support (O&S) costs over the life of the truck can be as high as or higher than the initial acquisition cost, the acquisition cost continues to create a constraint when limited budgets are applied at the individual platform level. Moreover, for fear of not winning a contract, major suppliers are reluctant to risk using new technologies that raise the initial cost and/or add risk to the development process.

RECOMMENDATION. THE ARMY SHOULD DEVELOP A LONG-RANGE, FLEET-LEVEL PORTFOLIO STRATEGY THAT ESTABLISHES A SCHEDULE FOR TRUCK ACQUISITION, REMANUFACTURE, AND REPLACEMENT.

Although contingent on future funding, the plan should establish priorities for vehicle replacement with specific requirements for performance, including vehicle weight and fuel consumption for each type of vehicle. In order to reduce the technology development cost burden typically placed on an individual vehicle program, the strategy should also establish a broad technology development program plan. A technology development program should be based on a budget process that prioritizes new technology development. The program should establish concept development activities leading to the fabrication of prototype vehicle demonstrators. In order to leverage resources outside the Army, the technology program should involve vehicle integrators, material and component suppliers, other branches of the Department of Defense, other government agencies, and any other key sources of technology. The accomplishments of existing government programs should be leveraged to the greatest extent possible.

Suppliers respond to solicitations with whatever legitimate means are at their disposal in an attempt to win contracts. This behavior is entirely appropriate in a competitive market. Therefore, the most effective way for the Army to influence the cost and performance of future truck designs is through the procurement process.

RECOMMENDATION. THE ARMY SHOULD MODIFY ITS BID SOLICITATION AND PROCUREMENT PROCESSES TO STIMULATE AND REINFORCE DESIRED REACTIONS, INCLUDING:

• The Army should clearly define the performance attributes that are important in its use of trucks. For example, if reduction of the logistical footprint is important, this attribute and its method of measure must be defined; if the total cost of ownership or life-cycle costs are important, these attributes should be defined. The bidding process should be structured to reward improvements in these performance attributes.

• The Army should provide minimum values or, preferably, scaled values for each performance attribute. For example, the value to the Army of reducing the logistical footprint or increasing fuel economy should be indicated.

• In selecting the winner of a competition, the Army should make certain that all performance attributes, including specifically the cost of ownership, are given their appropriate weighting in the decision.

• The Army should develop and adopt a consistent life-cycle costing methodology for evaluating alternative technologies. At a minimum, energy costs, maintenance costs, and end-of-life costs should be incorporated into this methodology. It should be emphasized in the request for proposals that life-cycle cost will be heavily weighted in the selection decision.

• Life-cycle costs should be extended to implement best-value procurement practices. The value of all performance attributes should be quantified and these metrics used to select the best-value truck to meet the Army’s needs.

• The Army should review and revise its needs regularly. The description of an ideal truck varies across time, geography, and need for use. The procurement process must be flexible and responsive to these changing demands.

The unique duty cycles and mission profiles of Army trucks constitute a special defense requirement. To respond to this requirement, the Army must take the lead in driving investments in new materials that have the potential to deliver competitive advantage in the logistics arena, supporting warfighters and combat equipment. At the same time, the Army can more actively leverage new materials and manufacturing technologies from the private and academic sectors by investing directly in research and development programs that lead to proof-of-concept demonstrations. The Army’s Small Business Innovative Research (SBIR) program is to be complimented; it should be kept well funded and targeted to the lightweight trucks initiative in order to encourage high-quality material and manufacturing innovations from academia and industry.

RECOMMENDATION. THE ARMY SHOULD LEVERAGE NEW COMMERCIAL MATERIALS AND MANUFACTURING TECHNOLOGIES TO ACCOMPLISH ITS GOALS OF IMPROVED MOBILITY, DURABILITY, AND FUEL EFFICIENCY IN NEW TACTICAL TRUCKS. TO ACCELERATE TECHNOLOGY TRANSITION, THE ARMY SHOULD PARTICIPATE IN COLLABORATIVE PROGRAMS WITH ADVANCED MATERIALS INDUSTRY CONSORTIA.

By leveraging commercial advances, the Army can evaluate the technical feasibility of new materials and technologies. Pilot demonstrations of new materials and technologies in Army applications could then be used to increase the knowledge and capabilities of the supplier base.

Additional leveraging opportunities for the Army exist in the form of industry-government programs sponsored by the Department of Energy and the Department of Commerce that have identified advanced materials for application development. The emphasis of participants from the commercial automotive industry on the affordability of new materials, such as titanium, magnesium, and polymer matrix composites, should greatly facilitate prudent investment decisions by the Army. By working more closely with university centers of excellence, the Army can identify new enabling technologies in lightweight materials and in sensing and health monitoring, and it can also fund demonstration projects.

The early involvement of key stakeholders—including suppliers, maintenance personnel, and end users—in decisions regarding new materials is essential. The Army should assign a larger role to its material and component suppliers, and perhaps provide incentives for using new materials and technologies. The cradle-to-grave research and development for processing, assembly, service, remanufacturing, and operator training, which is currently done primarily within the Army, should be shifted to establish a more collaborative approach with these material and component suppliers.

Army trucks are kept in service far beyond their economically useful life, resulting in increased operations and support costs and decreased performance. The effectiveness ratio of the total Army tactical wheeled vehicle fleet was recently calculated to be about 0.63 (compared with 1.0 for a new fleet). Effectively, eight existing trucks are required to do the work of five new ones. In addition, the annual total operating and maintenance cost for the Army truck fleet is about $1.5 billion, or more than $6,000 per truck. These costs are increasing at a rate of about $30 million per year, while the fleet size is being reduced from about 250,000 to about 225,000 trucks.³ Other data indicate that a large fraction of these costs are for corrosion repair. The economically useful life of a truck has recently been estimated to be about 13 to 16 years, at which point the effectiveness ratio is reduced to 0.5.⁴ Retirement and/or replacement should be considered at this age.

RECOMMENDATION. THE ARMY SHOULD ESTABLISH A MECHANISM FOR RETIRING OLDER TRUCKS AND FOR REPLACING TRUCKS IN POOR CONDITION WHEN THE AVERAGE YEARLY MAINTENANCE COST BECOMES PROHIBITIVELY HIGH.

A centralized tracking system could be used to record the present position of every truck in the fleet and to ensure that trucks were retired and/or replaced on a regular basis. (Both Federal Express and United Parcel Service use such tracking systems for their trucks.) Such a system could also

be used to select trucks for participation in recapitalization programs. Currently, the age and condition of Army trucks sent to such programs varies widely (Hathaway, 2001). Data on repairs and parts failure could be shared with manufacturers in order to facilitate design improvements. A more standardized system for the replacement of damaged trucks would promote the introduction of new materials and technologies into the truck fleet.

The majority of material used in Army trucks today is plain carbon steel. The corrosive galvanic current between two plain carbon steel parts placed in contact will be small and may not cause serious corrosion. However, as more new materials are introduced into Army trucks, galvanic isolation between parts made from widely differing materials will become increasingly necessary. The inspection, maintenance, and repair procedures for vehicles with such parts will become increasingly complex.

RECOMMENDATION. THE ARMY SHOULD INSTITUTE A MECHANISM FOR ENSURING THAT DIFFERENT TYPES OF MATERIALS ARE TRACKED DURING REPAIR AND DISPOSAL.

A color code or a numbering code that provides each alloy with its own identification is one such mechanism. A coding system could clearly indicate to those making field repairs where galvanic corrosion would occur and where it would be vital to provide galvanic isolation. (As an example, if all steel parts were coded with one color and all parts made of cast aluminum were coded with another color, it would be obvious which parts needed to be isolated.)

As different materials are increasingly used on Army vehicles, repair and replacement procedures will become more complicated. For example, composites are a class of materials now being selectively used in Army trucks— repair procedures for these materials are not generally known and are very different from those for metallic materials. Maintenance training will be required for each new generation of vehicles. In addition, as some parts are changed during recapitalization programs, maintenance and repair manuals will need to be continuously updated. Computerization of future depot maintenance manuals would aid in their being kept current for purposes of repair. Vehicle OEMs (original equipment manufacturers) could

be required to maintain these manuals, as well as information on common parts failures, on their Web sites.