Is the flux used for the purification of aluminum melt OK

Fluxes can be used for the purification of aluminum melt. ‌

In the process of aluminum alloy melting, ‌ hydrogen and oxide inclusion are the main substances polluting aluminum melt. ‌ flux refining is a common purification method. ‌ is mainly by adding appropriate flux to the melt, ‌ will react physically and chemically with impurities in the melt, ‌ will form light solid phase components into the slag, ‌ will be removed in the slag operation, ‌ so that the melt can be purified. ‌ This method can effectively remove oxidizing inclusions and some gases ‌ though not clean. ‌

The commonly used refining agent is based on chloride. ‌ adds fluoride such as CaF2, ‌Na3AlF6, etc. to adsorb, ‌ dissolves Al2O3, and ‌ to increase the purification effect. ‌ These fluxes are sprinkled on the surface of the aluminum alloy melt during refining, ‌ because they are less dense than liquid aluminum ‌ they float on top. ‌ After stirring and resting, ‌ remove the slag above the alloy and sprinkle a layer of covering agent, ‌ refining can be poured 1. ‌

In addition, ‌ there have been studies on the use of a mixture of chlorine and nitrogen to purify liquid aluminum. ‌ on the one hand, this method removes hydrogen and separates oxides, ‌ on the other hand, removes some metallic impurities (‌ such as magnesium) ‌ from aluminum. ‌ is commonly used as 90% nitrogen +10% chlorine gas, ‌ is also used as 10% chlorine +10% carbon dioxide +80% nitrogen combination, ‌ carbon dioxide to make chlorine and nitrogen better diffusion, ‌ shorten the operation time. ‌

In summary, ‌ flux plays an important role in the purification of aluminum melt. ‌ through the physicochemical reaction and adsorption dissolution, ‌ can effectively remove impurities and gases in aluminum melt, ‌ thus improving the quality and properties of aluminum and aluminum alloys. ‌