Flux classification: There are many types of fluxes used in aluminum alloy smelting, which can be divided into two categories: covering flux (flux to prevent melt oxidation and burning and gas absorption) and refining agent (flux for degassing and removing inclusions). The covering flux and refining agent used in the aluminum alloy are different.
Requirements for the flux:
1. The melting point should be lower than the melting temperature of aluminum alloy.
2. The specific gravity should be less than that of aluminum alloy.
3. It can absorb and melt the inclusions in the melt, and can remove the gas from the melt.
4. It should not chemically interact with metal and furnace lining. If it interacts with metal, it should only produce inert gas that does not melt in the metal, and the flux should not melt in the molten metal.
5. The hygroscopicity should be small, and the evaporation pressure should be low.
6. It should not contain or produce harmful impurities and gases.
7. It must have proper viscosity and fluidity.
8. It is easy to manufacture with low price.