Adding the flux for refinement to refinement manner of the aluminum alloy hot water, and the aluminum

摘要

PROBLEM TO BE SOLVED: To remove the gas and impurities at high removal level by adding alum flux to a molten aluminum alloy in which raw Al is melted. ;SOLUTION: Alum flux is formed of single alum, or through combination of alum with other flux such as potassium sulfate. Al alloy cast ingot having the composition consisting of ≤0.25 cc/100 g Al H2, and ≤200 ppm oxide including MgO, Al2O3, and spinel is melted in a melting furnace. Alum flux of 1-0.01 mass % to the molten Al alloy is blown together with the inert gas such as N2. The alum flux decomposes and emits Sox such as sulfate and So2 at the temperature of 700°C of the molten Al alloy. The Sox gas takes in H2 gas in the molten metal in bubbles, and is afloat on the surface of the molten metal in a fugacious manner to remove H2 gas in the molten metal. The impurities in the molten metal are afloat on the surface of the molten metal due to the stirring effect and the floating effect of the generated Sox gas and the inert gas, and removed from the molten metal through the accelerated slag condition.;COPYRIGHT: (C)2000,JPO