Method Of Component Materials Selection In AutoBody Concept Design Stage Using Simplified Models

As one of the pillar industries, the automotive industry plays an important role topromote the development of both the national economy and the society. Although, China hasbecome the world’s largest car producer, there is still big gap between China and other carproducing countries like the United States, due to the weak ability of undertakingindependent research especially on automotive bodies. One of the solutions to this problemis to make reasonable choice of materials for automotive bodies, which is a prerequisite ofproducing automotive bodies with good performance.Material selection is a significant and complicated step during automotive body design.There are many performance related factors such as the stiffness, the intrinsic frequency, andother factors like price, material quality, retrievability and anti-corrosion that should beconsidered carefully before making the final decision. At present, the concept design ofautomotive body is increasing important. The blindness of design revision can be avoidedand the development cycle can be shortened effectively if material selection is carried out atthe concept design stage of automotive bodies. At this stage, models with detailedparameters are normally unavailable for the sake of simplification.On the basis of using materials at right places, a material selection methodology isproposed in this paper. It studies how to make best choice of materials for differentautomotive body parts and provides guidance for subsequent design by giving specificrecommendations based on simplified models. The material selection system presented inthis thesis can shorten the cycle and elevate the efficiency of the concept design of anautomotive body. A simplified model mixing with beams and shells is built, with B pillar andthe hood representing beams and shells in the model for the study and verification of the proposed material selection system. This thesis provides initial design scheme for the‘Material selection system (MSS) for the concept design of automotive body’, and severalinterfaces was designed. The structure of the thesis is as follows:1)The background of proposed research is illustrated by analysing the state-of-the-art ofmaterial using, material selection methods and the function of simplified models in theautomotive industry. Accordingly, the importance and research content are presented.2)The material selection system is proposed, and the properties of commonly usedmaterials are introduced as well. For the sake of preparation for the subsequent analyses, thesimplified models mixing beams and shells are created, and the corresponding formulae arederived.3)B pillar and the hood are chosen as representatives of the simplified models forbending and torsional stiffness and natural frequency evaluations under different loadingconditions. The results are compared with that of the detailed models. By choosing R2as theevaluation parameter, and regression analysis as the method, comparison study is carried out.The results show that the stiffness derived by both the simplified and detailed models havesimilar trend, although there are big differences in terms of performance indicator, whichmeans that the proposed method is effective.4)For the sake of elevating work efficiency, initial design of the MSS is carried out.Firstly, the requirement of the MSS is analysed. Then the overall functions and workprocedure is introduced. Finally, the user graphical interfaces are designed using Matlab, andtheir major functions are explained.The proposed research shows that: it is possible to use the simplified models instead ofthe detailed models for carrying out material selection during the concept design ofbenchmarking of an automotive body. The integration of material selection process into usergraphical interfaces will benefit the design of automotive bodies by shortening thedevelopment cycle.