Study On Material Selection For Key Components Of Auto Body

With the development of material science, there are more and more materials used in human s daily life. And the process of them are becoming varied, which has also brought great changes to the materials of body components at the same time, so that the steel structure gradually take the place of the wood structure, and the structure made of variable materials will be the direction of body s future. However, the innovation brings up two disadvantages: One is that the number of materials which can be used in body components increases from dozens to thousands such that the size of relevant data is huge. The other is that there are complex relationships between the data and parameters of design, manufacture and cost. The material selection of body components becomes exceptionally difficult because of these defects.In order to solve this problem, this paper did some research in material selection of body components based on Ashby theory. At the beginning of research, the in-depth analysis of Ashby theory was made, and concluded two defects from the process of selection: Oneness and Feasibility of material indices. Weighting Ashby theory and Mapping method based on materials library were put forward aimed at the defects. The former combined the traditional Ashby theory which referred to the single performance with expert grading method so that the rank of material could be equivalent to score. The weighted values reflecting the focus of performance which designer cares for was also applied to the weighting Ashby theory, and the final solution could be acquired by the score and the weighted values, application in selection material of outer panel of front door shows that weighting Ashby theory is very effective. The core of the latter was the idea of material indices which had been put forward in Ashby theory, in this method, the performance of real component within different materials could be forecast by the mapping relationships between real component and reference component in structure and material so that the solution would be obtained. The result of application in optimization of the front rail indicates that mapping method based on materials library is a fruitful method.