When the aluminum alloy melts, the molten metal casting flux is used to eliminate the hydrogen that forms pores when the molten aluminum alloy solidifies, and to clean the molten aluminum alloy by eliminating non-metallic inclusions that cause internal defects.
In recent years, from the perspective of resource conservation and cost reduction, the recycling of aluminum alloys has become common. Since different alloys have different content of added elements, aluminum alloys are recycled in secondary aluminum alloys and cast aluminum alloys whose composition is easy to adjust.
The recovered scrap is melted in the molten metal through the smelting process, the molten metal is refined through the refining process, the slag is removed from the refined molten metal through the slagging process, and the refined molten metal is cast to provide secondary alloys or casting alloys.
The material placed in the furnace, that is, scrap is heated and melted to produce molten metal. The organic matter adhering to the material and the oxide produced during the melting process form various inclusions in the molten metal. Inclusions and metals are mixed to form slag under the agent of the refinery, and the slag floats up. Slag is the main cause of product defects and therefore must be removed. However, since the slag contains metals with high metal content, metal loss will occur if the metal-containing slag is removed. Therefore, the metal contained in the slag must be returned to the molten metal as much as possible, and only the inclusions must be effectively removed through the slagging process.
A slagging process sprays the metal casting flux onto the surface of the molten metal, so that the flux and the slag are mixed. The aluminum casting flux reacts with the fine aluminum particles contained in the slag. The reaction generates reaction heat, which heats the slag to enhance the fluidity of the metal contained in the slag, and returns the metal to the molten metal. The generally known degassing process blows the flux into the molten metal together with an inert gas such as nitrogen or argon. The degassing process and the slagging process are very important metal liquid processing processes, which can purify the metal liquid and improve the product quality. The slagging agent used to remove slag from molten aluminum alloy.
