Among the lightweight metals, although the density of magnesium alloy is smaller than that of aluminum alloy, the cost of magnesium ingot is higher, and there are many technical obstacles in the parts manufacturing process, such as lack of high-temperature die-casting alloy and design data, poor surface treatment technology, and low level of bonding, Etc., so the current usage in cars is quite limited. Although titanium alloys used in aerospace and aerospace have high mechanical strength, manufacturing processes are difficult and expensive, the titanium alloys cannot be used in automobile production in large quantities. Aluminum alloy has good comprehensive performance in terms of cost, manufacturing technology, mechanical properties, sustainable development (the most aluminum content in the earth’s crust, accounting for 8.1%), and other aspects. Therefore, aluminum alloy is the preferred light metal material in the automotive industry now and in the future.
The application of aluminum alloy to automobiles not only has obvious effects of weight reduction and energy saving, but also conforms to the development trend of safety, environmental protection, and automobile materials, and has significant economic and social benefits. Since the weight of the car body plays a decisive role in the whole vehicle, the development of high-performance and distinctive car body panels is an important link in the process of my country’s automobile lightweight.
Advantages of automotive aluminum alloy
1. Comply with the global environmental protection concept. The improvement and advancement of smelting technology will increase productivity, so the unit price of aluminum alloy will continue to decline, and the environmental protection concept of governments and people around the world will gradually increase. Therefore, automakers will be strongly required to adopt changes in technology and cost. More aluminum alloys.
2. Automotive aluminum alloy is easy to improve the stamping and forming ability. Aiming at the problem of low stamping performance of aluminum alloy sheets, on the one hand, we can rationally optimize the ratio of each alloy element through material science research, and improve the overall performance of the alloy through reasonable ratio and interaction between the elements. On the one hand, it can improve the process, such as the heat treatment process and rolling process to improve the stamping and forming ability of the aluminum alloy sheet.
3. Obvious effects of weight reduction and energy saving. Aluminum has good mechanical properties. Its density is only 1/3 of that of steel. It has good thermal conductivity, second only to copper, and its machining performance is 4.5 times higher than that of iron. The oxide film naturally formed on its surface has good corrosion resistance. Therefore, aluminum has become the most ideal material of choice for lightweighting automobiles.
4. The comfort and safety of passengers are improved. Aluminum alloy cars reduce the weight of the car without reducing the capacity of the car, the center of gravity of the body is reduced, and the car runs more stable and comfortable. Due to the good energy absorption of aluminum, it has obvious advantages in collision safety. The deformation zone at the front of the car will produce wrinkles during a collision, which can absorb a large amount of impact, thereby protecting the driver and passengers behind.
5. An automotive aluminum alloy is easy to recycle. Aluminum products rarely corrode or only slightly corrode during use. Among the conventional materials used in industry, aluminum has the highest recovery value rate. In the recycling process of aluminum material—aluminum product recycling aluminum ingot—reprocessing into aluminum material, the loss of aluminum is only about 5%, and its recycling performance is higher than that of any common metal.
At present, my country’s automobile production volume ranks fourth in the world after the United States, Japan, and Germany. In terms of the auto aluminization rate, my country’s technology is still relatively backward. At present, the use of aluminum in automobiles in developed countries has reached 138kg, and the aluminization rate has reached 12%. However, the use of aluminum in automobiles in my country is far behind foreign countries. The average aluminum consumption is only 60kg, and the aluminization rate is less than 5%. Therefore, the development prospect of my country’s automotive aluminum alloy market is very broad.