cast aluminum is a kind of handicraft, which is used especially widely. The surface treatment of non-ferrous metal castings, casting, aluminum, automobile parts, hardware, and pump valve industry will be used.

    cast aluminum parts contain free silicon besides, there are many compounds and other inclusions between metals. Because of the loose microstructure of the cast aluminum, it is possible that the chemical composition segregation is not uniform, and the unprocessed surface will form a dense oxide film when cast after casting. The time of alkali corrosion is short, then the cast aluminum may not be completely eliminated, and the dissolution rate of cast aluminum is faster because of alkali corrosion. The corrosion of cast aluminum is often caused by alkali corrosion, which causes the change of tolerance size and even cause the product to be scrapped.

    in view of the above situation, it is possible to change the alkali corrosion procedure to solve the problem of alkali etching after casting. The operation of this process can not only prevent the occurrence of corrosion caused by alkali corrosion, but also improve the surface quality after oxidation.

    adopting the above alkaline etching method can avoid the corrosion of the parts. After alkali corrosion, the rapid light out of 2 ~ 3S can be used in the hydrochloric acid of 1:1 to replace the toxic hydrofluoric acid, which not only benefits the environmental protection, improve the labor conditions, but also reduce the production cost.