Research On Application Of High Strength Steel In Automotive Lightweight

With the ever-increasing volume of cars, energy shortage, environmental pollution and other issues are becoming more prominent, energy conservation and environmental protection have become important problems relating to sustainable development of human, energy-saving and emission reduction have been the problems crying out for solutions for automotive industry.In this paper, the floor of a heavy truck cab was taken as study object, the lightweight goal was hoped to be achieved through selecting high strength steel and aluminum alloy material to change the thickness, and lightweight research was done for main components.(1)According to the characteristics of research on lightweight of automotive body structure , a variety of lightweight materials and their applications were systematically analyzed, focused on the characteristics of high strength steel and its application.(2) Basic theory of finite element method and finite element analysis softwares were discussed , finite element model of the floor of a heavy truck cab was created. The modeling process should pay attention to the problems of CAE modeling, including the collation of the geometric model, element selection, spot treatment, and quality index of evaluating model was analyzed.(3) Principles of linear static analysis were introduced , including static strength and stiffness analysis. Then deformation and stress of the floor were calculated and analyzed in conditions of bending and torsion, and the evaluation results were made, the finite element model was verified correct through continuity of the bending deflection curve of the floor's longeron .On this basis, high strength steel was used to reduce thickness of the floor for five main parts lightweight research, both the stiffness and strength were compared, then feasible lightweight program was brought out.(4)Aluminum alloy material was used to do lightweight research, and then was compared with the lightweight program of high strength steel plate. First of all, the characteristics of different series of aluminum alloy ware discussed, aluminum alloy used for the lightweight study of body was selected, according to thickness ratio and mass ratio with steel under the same bending stiffness and bending strength, thickness of five parts was modified, the viable lightweight program was come to. Finally, cost-effective of three materials' lightweight program was compared, ordinary low-carbon steel, high strength steel and aluminum alloy material.The above mentioned studies have shown that the use of aluminum alloy materials and high strength steel plate can achieve lightweight of vehicle structure, the effect of lightweight of aluminum alloy material is better. Although there is a certain gap between high strength steel plate and aluminum alloy about effect of weight loss, it has the characteristics of lower cost of production, mature processing technology, so the use of high strength steel has a certain advantage. Lightweight research can be extended to the entire cab, frame, light carriage, etc. Overall weight of the truck can be reduced.