Case studies of materials selection and design
Ten detailed practical examples, or case studies, have been chosen to explain and impart a better understanding of the methods described in the previous chapters. The first example describes the problem of selecting materials for a hip joint prosthesis, which includes target criteria. The process of obtaining three types of weightings, ranking with comprehensive VIKOR and extended TOPSIS methods, and the aggregation process for optimal materials selection has been exhibited in this example. The second example, which includes the target value of criteria as well as interval data in some criteria, describes the problem of selecting materials for the femoral component of a total knee replacement. The third to fifth examples are all related to materials selection and design of knee prostheses. The third example is the design and multi objective optimization of a functionally graded material for the femoral component of knee prosthesis. The fourth example deals with materials selection and design optimization problem, and the fifth example is a simultaneous material and design selection problem, while demonstrating the role of quality function deployment (QFD) in design decision making. The sixth example is a typical engineering problem, selecting materials using interval data, in this case to repair aircraft structures. The seventh example uses a mechanical turnbuckle assembly to introduce the concept of multiple component materials selection. In addition, it tries to reveal cost uncertainty in the early stages of the design process. The eighth example explains the place of multiple attribute decision making (MADM) in the lightweight design of a thin walled tube for the energy absorption structure in a motorcar. A strategy for decision making, in the presence of a difference between physical and simulation experiments, is also highlighted in this example. The ninth example describes the use of fuzzy MADM when selecting materials for a motorcar dashboard. The last example discusses selecting hard coating materials to resist wear.