Materials selection, life-cycle considerations

Abstract Whereas much attention has been paid to the environmental aspects of the life cycle of fuel cell fuel production, emphasis is placed on fuel cell hardware and materials recovery, including component reuse, remanufacturing, materials recycling and energy recovery for fuel cell maintenance and retirement processes. Fuel cell hardware recycling is described and issues related to the recycling infrastructure and the compatibihty of fuel cell hardware and materials are discussed. The role of materials selection and recovery in the fuel cell hfe cycle is described. Future trends for fuel cells centered on voluntary and mandatory recovery and the movement of life cycle considerations from computational research laboratories to design complete the discussion. 

There are no simple rules of thumb in defining the cost of reinforced plastic components. Their successful use has resulted from proper design, utilizing the benefits these materials offer, process selection, tooling cost advantages that fit the production needs, and consideration of life cycle economics. Each existing application illustrates the cost-performance advantage of reinforced plastic over the traditional material that is displaced. 

Selection of fluoropolymers is an integral part of the overall material selection process. This implies that all the available materials such metals, ceramics, and plastics are considered candidates for an application. The end user then considers these materials against established criteria such as required life, mean time between inspection (MTBI), ease of fabrication, frequency of inspection, extent of maintenance and, of course, capital cost. More often than not it is the initial capital cost, rather than the life cycle cost of equipment, that affects the decision made during the material selection step. However, the most important piece of data is the corrosion resistance of a material in the medium under consideration over the life of the equipment. This information is available in a different format for plastics than for metals. A comparison is appropriate. 

The available data from the services indicate that corrosion in weapons systems is the primary cost driver in life-cycle costs (46). Quantifying corrosion is difficult as neither the mechanisms nor the methodologies exist to quantify accurately. Analysis of field data reveals instances where questionable materials selection early in the acquisition process has led to enormous unanticipated increases in life-cycle costs because of corrosion (J Argento, US Army TACOM-ARDEC, Picatinny Arsenal, NJ, Personal Communication, 1999). In view of force reduction and a reduction in budgets, consideration must be given to the selection of advanced materials, processes, and designs that will require less manpower for corrosion inspection and maintenance. 

R. W. Chen, D. Navin-Chandra, 1. Nair, and F. Prinz, ImSelection-An Approach to Material Selection that Integrates Mechanical Design and Life Cycle Environmental Considerations in proceedings of IEEE International Symposium on Electronics and the Environment, Orlando, USA, IEEE, Piscataway, NJ, USA (1995). 

Selecting an elastomer for an application requires consideration (like for plastics and foams) of many factors, including the mechanical and physical service requirements, the product s life cycle, the material s processability, and its cost (see Figs. 6-24 and 6-25 and Tables 6-12 and 6-13). A wide range of properties is available, based on the many different compounds that can be produced. 

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