331Materials Selection Process
The fuzzy set approach deals with vague and imprecise material properties, such
as weldability, corrosion resistance, and wear resistance. Properties of this type are
normally given discrete values. For example, excellent (5), very good (4), good (3),
fair (2), or poor (1). Fuzzy logic on the other hand allows for values between the
discreet numbers. In other words, the value of a classical variable can be restricted
to either 1 or 0, which is either accept or reject; a fuzzy variable can have any value
between 0 and 1, which corresponds to various shades of acceptance or rejection.
Multi-objective optimization methods can be used readily in selecting materials
and processes for a given design. The goal in sel ...