The mass fraction of Mg in Al-Mg alloy is 4%~11%. The alloy has low density, high mechanical properties, excellent corrosion resistance, good machinability and bright and beautiful machining surface. However, due to the complex smelting and casting process, this kind of alloy is not only used as corrosion resistant alloy, but also as decorative alloy. The characteristics and applications of common cast Al-Mg alloys are as follows.
1. ZL301 alloy ZL301 alloy with high strength, good percentage elongation, good machinability, good weldability, can be anodized, shock, the disadvantage is that have a tendency to microporosity, cast difficult ZL301 alloy used in the manufacture of high load, working temperature below 150 degrees Celsius, and to work in the atmosphere and seawater corrosion resistance high parts, Such as frames, supports, bars and accessories, etc.
2.ZL303 alloy ZL303 alloy has good corrosion resistance, good weldability, good machinability, easy polishing, casting performance is ok, mechanical properties are low, can not heat treatment strengthening, there is a tendency to form shrinkage cavity, widely used in die casting. These alloys are mainly used in parts with moderate loads under corrosion or in cold atmospheres with operating temperatures not exceeding 200 degrees Celsius, such as sea vessel parts and machine housings.
ZL305 alloy is mainly based on al-Mg alloy by adding Zn, control the natural aging, improve the strength and stress corrosion resistance, has good comprehensive mechanical properties, reduce the alloy oxidation, porosity and porosity defects. This kind of alloy is mainly used to withstand high load, working temperature below 100 degrees Celsius, and in the atmosphere or seawater work requires high corrosive parts, such as Marine ship parts.