With the improvement of automobile lightweight requirements, more and more automobile aluminum alloy parts, the cast iron materials used in the past have been gradually replaced by aluminum alloy materials, so the market performance requirements for aluminum alloy die casting parts are also getting higher and higher.

Aluminum alloy die-casting parts have high strength, good corrosion resistance, good thermal conductivity, good casting processing performance, and lower production costs than other types of aluminum alloys. Aluminum alloy die-casting metal elements can change the properties of the material. It is already automotive, communications electronics and aerospace. Die cast aluminum AlSi10MnMg is a high strength, toughness and heat treatment cast aluminum alloy of Al-Si-Mg-Mn system. It has good air tightness, fluidity, high density and strength, and strong corrosion resistance.

The porosity of welded joints of aluminum alloy die-casting products is mainly hydrogen porosity. The hydrogen porosity is produced by the welding material and the base material of the welding joint melting to form a molten pool at high temperature. The temperature of the molten pool formed by these molten metals is very high, and the solubility of hydrogen dissolves a large amount of hydrogen in the aluminum alloy die-casting molten pool with the rapid rise of temperature. After the arc leaves, the temperature of the molten pool drops rapidly. At this time, with the decrease of temperature, the solubility of hydrogen drops sharply, and a large amount of hydrogen spills, but the crystallization rate of aluminum is a block, and the density of aluminum alloy is small, so the buoyancy of the bubbles formed in the molten pool is small.

Aluminum alloy die casting should not only have excellent die casting process and mechanical properties, but also have the following process properties:

① It has good thermoplastic rheological properties. It has good thermoplastic rheological properties near the temperature of the liquid and solid phase line, realizes complex cavity filling, forms a good casting surface, and avoids shrinkage defects.

② Small yarn shrinkage, avoid aluminum alloy die-casting cracks and deformation, improve product dimensional accuracy.

③ In a small solidification temperature range, it is easy to solidify quickly at the same time, reducing the number of defects such as internal shrinkage holes.

④ High temperature thermal strength is good to avoid hot cracks and large deformation during die casting of aluminum alloy.

⑤ Casting interface performance is good. No chemical reaction with the die casting mold, small affinity, to avoid the alloy reaction at the casting interface.

The good physical and chemical properties make it difficult to inhale oxidation of aluminum alloy die-casting at high temperature melting state, which can meet the needs of long-term thermal insulation of die-casting process.