A new application of ELECTRE III and revised Simos' procedure for group material selection under weighting uncertainty

Towards the end of a design process designers may face a number of candidate materials with different attributes that are difficult to distinguish with the aid of available databases. In such situations material selection of sensitive components is perhaps one of the most challenging problems in the design of structural elements in some industries such as aerospace. The selection process is often realized as a team-work task to enhance reliability of the chosen material. During group decision making, however, separations in design preferences can be encountered. Furthermore, there may be uncertainties in each designer's mind with regards to expressing his/her preferences over design criteria. This paper using a revised Simos' method with the ELECTRE III optimization model is an attempt to provide a decision aid framework that account for both of these effects. A post-aggregation strategy with an overall rank loss function is proposed to arrive at candidate materials that show the most stable and the highest ranks in a list of given candidates. To show the applicability of the approach, a sample case study in the material selection of a thermal loaded conductor cover sheet is conducted and validated by an available database. It is also illustrated that, using ELECTRE III, a non-compensatory aspect of material selection can be assumed while attaining a reasonable sensitivity to weight fluctuations.