A method for optimal material selection aided with decision making theory

As a CAE (Computer Aided Engineering) tool to help design engineers, the procedure of material selection should be objective so as to minimize personal bias and it should be able to be coded into the software of ‘expert system’. In this work, we have utilized the theories of decision-making. One of them is the concept of entropy; to evaluate the weight factor for each material property or performance index, and the other is TOPIS; to rank the candidate materials, for which several requirements are considered simultaneously. As an example, the procedure to select the optimal material for a flywheel has been developed. We can grade the candidate materials for given subjective weight. In the cases for which fatigue strength or fracture toughness is weighted, the chosen materials coincide with the ones utilized for a commercial flywheel in support of our approach.