Research Of Multi-material Optimization Based On Recycling

Material selection is one of the important stage in the product d esign phase. With the rapid development of automobile industry, car ownership and the number of end-of-life vehicles are increasing. And which cause the environment, resources and other issues have received more and more attention. Therefore considering th e recycling property of the vehicle products in the product design phase, which is very important for protecting the environment and conserving natural resources. There are lots of researches on multi-material in the product design phase, but these researches do not consider the recycling performance of vehicle materials. In this paper, the multi-material optimized selection is considering the recycling of vehicle products based on the researches of previous scholars.Because the recycling performance is a qualitative parameters, so by consulting and summarizing relevant literatures, the material handling, the material combination, the connection type, the recycling equipment and the recycling profit are taken as the key factors which influence recycling parameters. Because these four factors are imprecise, therefore this paper divides the four factors into different level according to certain fuzzy criterion. Assigning different membership scale to every level of the four factors and determining the weight coefficients of the four factors on the recycling value using Fuzzy Analytical Hierarc hy Process, by using the linear weighted sum of these four fuzzy factors to represent the recycling value.The recycling value and the recycling profit are used to assess recycling performance of the vehicle products. So in this paper constraining the performance of vehicle structure. The material type and the geometrical parameters of vehicle components grouped together constitute the design variable space as the design variables by assigning a unique identifier encoded to the material type. And considering the body quality, cost, recycling value and recycling profit, and establishing a mathematical model for multi-material optimization problems based on recycling. And using multi-objective genetic algorithm NSGA-â…¡ to optimize the mathematical model.Taking a vehicle hood as an example, constraining the torsional stiffness and the constraint mode of the hood and establishing an optimization mathematical model to optimize the material type and thickness of the inner and outer panel of the hood. And obtaining the best material combination scheme of the inner and outer panel of the hood. Establishing the finite element model of the hood and analyzing the tor sional stiffness and the constraint mode of the hood selecting the best material combination scheme of the inner and outer panel. And testing the torsional stiffness and the constraint mode of the hood by designing and setting up the test bench. Comparison of simulation and test results, it verifies the feasibility of the method of multi-material optimization based on recycling, and provides a new idea for the optimization and selection of material for vehicle products.