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Refining agent is a product commonly used in industry, but there are various problems and types in oxides. Here is a brief explanation. The type of high-performance aluminum alloy refining agent with oxide inclusions.

Types of oxide inclusions

During the disposal and transportation of molten metal, foreign matter such as oxide scales, intermetallic compounds, and hearth fragments are easily brought into the molten metal to form non-metallic inclusions. These non-metallic inclusions are mainly oxide inclusions. According to the difference of its formation period in the coagulation and casting process, it can be divided into primary oxide inclusions and secondary oxide inclusions.

The primary oxide inclusions of the refining agent mainly refer to all the oxide inclusions formed before the molten aluminum is poured. Primary oxide inclusions can be divided into two categories according to their appearance: one is large inclusions that are unevenly dispersed in the macrostructure. This type of inclusion makes the alloy structure discontinuous, reduces the air tightness of the workpiece, and becomes the source of corrosion. Significantly reduce the strength and plasticity of aluminum alloys, and often become the source of cracks in parts. *The second type of oxide inclusions refers to small, dispersed inclusions that cannot be completely removed even after careful purification. It makes the molten metal viscosity maximum. Reduce the feeding ability of molten aluminum during solidification, and it is easy to form shrinkage porosity of castings.

Refining agent secondary oxide inclusions, also called endogenous inclusions, are mainly formed during the pouring process. Generally speaking, endogenous inclusions are relatively evenly distributed, and their particles are relatively small. The splash and turbulence of molten aluminum during the casting process are the main sources of secondary oxide inclusions. In the sand mold, the molten aluminum interacts with the moisture in the molding sand, and is synthesized into oxygen and hydrogen through hydration. Oxygen and aluminum form oxide inclusions, and the hydrogen dissolves in the molten aluminum.