There are more than 1,000 aluminum alloy* grades registered internationally, and each grade has multiple states, and there are obvious differences in hardness, strength, corrosion resistance, processability, adhesion, and decoration. When choosing the grade and state of aluminum alloy, it is difficult to meet all the above aspects at the same time, and it is not necessary. The priority of various properties should be set according to the product performance requirements, use environment, processing process and other factors, so as to be reasonable Material selection, reasonable cost control under the premise of ensuring performance.

Many customers are very concerned about the hardness when buying aluminum. The hardness is directly related to the chemical composition of the alloy. Secondly, different conditions also have a greater impact. In terms of the highest hardness that can be achieved, the 7 series, 2 series, 4 series, 6 series, 5 series, 3 series, and 1 series decrease in order.

Strength is an important factor that must be considered during product design. Especially when aluminum alloy components are used as structural parts, appropriate alloys should be selected according to the pressure they bear. Pure aluminum has the lowest strength, while the 2 series and 7 series heat-treated alloys have the highest strength. There is a certain positive correlation between hardness and strength.

Corrosion resistance includes chemical corrosion resistance, electrochemical corrosion resistance, and stress corrosion resistance. Generally speaking, pure aluminum of series 1 has the best corrosion resistance, series 5 performs well, followed by series 3 and 6, and series 2 and 7 are inferior. The selection principle of corrosion resistance should be determined according to its use occasion. High-strength alloys are used in corrosive environments, and various anti-corrosion composite materials must be used.

Machining performance includes forming performance and cutting performance. Because the formability is related to the state, after selecting the aluminum alloy* grade, the strength range of various states needs to be considered. Generally, high-strength materials are not easy to form. If the aluminum material is to be formed by bending, stretching, deep drawing, etc., the formability of the material in the fully annealed state is the best, on the contrary, the formability of the material in the heat-treated state is *poor. The cutting performance of aluminum alloy has a great relationship with the alloy composition. Generally, aluminum alloys with higher strength have better machinability, and on the contrary, lower strength ones have poorer machinability. For products that require cutting, such as molds and mechanical parts, the machinability of aluminum alloys is an important consideration.

Most aluminum alloys have no problems with the connection, especially some 5 series aluminum alloys, which are designed for the connection. Relatively speaking, some 2 series and 7 series aluminum alloys are more difficult to connect.

When aluminum is used for decoration or some special occasions, the surface needs to be processed by oxidation, coating, etc. to obtain the corresponding color and surface structure. At this time, its decoration should be considered. Generally speaking, the materials with better corrosion resistance have very good color treatment performance, surface treatment performance and coating performance.