At present,the automobile industry has become the pillar industry of China,especially after 2000,China's automobile industry has entered the fast lane,and has become the world's automobile production country and the world's more potential consumer market.Lightweight is an important means of energy saving and emission reduction in the automobile industry, and lightweight will inevitably lead to a large number of applications of aluminum alloy in the automobile. The weight reduction effect of typical aluminum parts can reach 30-40% at a time, and the weight reduction can be further increased to 50% at a second time. When the weight of the automobile is reduced by 10%,more fuel saving 8% can be achieved. It can reduce 20kg exhaust emission during the life of car.At the same time,aluminum is a green environmental protection material, easy to recycle, recycling, using aluminum to save energy is the production of the parts used in the original aluminum energy consumption of 6-12 times.Current aluminum alloy applications in automotive include: aluminum alloy sheet for body panels,extruded profiles, aluminum alloy composite materials and other applications.