ABSTRACT
Materials substitution is an ongoing process and the materials used for a given product should be reviewed on a regular basis using a materials audit process. Decisions to substitute a new material for an established one, should consider the risks involved, the cost of conversion, equipment needed, and the environmental impact. The processes of substitution can be conveniently divided into creating alternatives, comparing and ranking alternative substitutes, and reaching a final decision. This chapter discusses several quantitative methods of substitution. The use of quantitative methods ensures that decisions are made rationally and that no viable alternative is ignored. Quantitative methods include Pugh's method for initial screening, cost of performance method, compound performance function (CPF) method, and the optimization toolbox of MATLAB ® for ranking alternative solutions, and cost–benefit analysis for reaching a final decision.
