Research Of Axial Crushing Of High Strength Aluminum Alloy Thin-Walled Structures Under Warm Forming

With the rapid development of automotive industry, the environment and energy of problem have become increasingly serious, even people come to realize the urgency and important of energy conservation and emission reduction, and the impact of lightweight. Aluminum alloys is the most prospect lightweight material, but the formability of aluminum alloys at normal temperature is very low. To solve it, Imperial College proposed and grew the HFQ, which also can reduce spring-back to ensure accuracy. With the popularity of automobile, it is convenient for us, but it also brings lots of traffic accident. Excellent structure design of automotive can effectively improve automotive crash safety. The thin-walled structure, represented by HAT sample, is the most commonly used design, which has many advantages, such as low weight, high energy absorption.Base on tensile test and microstructure, the basic mechanics properties of 7075 in different HFQ is researched. The best HFQ technology of 7075 is obtained, and it is explained by microstructure analysis. Then by thermal-mechanical tensile test, the basic mechanics properties of 7075 at different temperature is researched. The result shows that the formability of 7075 is pretty good at high temperature. Base on starnping simulation and experiment, the formability of 7075 is researched. The result shows that the formability of 7075 is very bad at room temperature, which the crack is appeared. HFQ is helpful to the formability of 7075, and with the increase of forming temperature, the formability is better.Secondly, based on quasi-static crushing experiment and simulation, the energy absorption property of 7075 HAT sample of different HFQ is researched. The result indicates that under certain conditions 7075-T6 has the best energy absorption property. Finally, based on experiment and simulation, the energy absorption property of HAT sample with different material is researched. The result shows that 7075 has the highest specific energy-absorption and promising future in applications to realize lightweight of automotive.