Method for improving corrosion resistance of cast iron casting

Abstract

The invention discloses a method for improving corrosion resistance of a cast iron casting, and belongs to the technical field of corrosion and wear resistance of metal materials. The method is to pour smelted cast iron metal liquid in a sand mold; the metal liquid connects two electrode terminals; after the casting is totally solidified, that is, the casting is cooled to reach solid-phase temperature, the sharp wave electric pulse is applied; and after the casting is cooled to below the solid-phase line temperature by 200-400 DEG C, the electric pulse is cut off, and the casting is cooled to reach the room temperature. As the electromigration effect of the electric pulse, the content of C elements in carbides in the cast iron casting is increased, and the content of Cr elements is reduced, but the content of the C elements in a basal body is reduced, and the content of the Cr elements is increased; and the electric pulse is applied to the cast iron casting containing a certain content of Cr to increase the electrode potential of the basal body structure of the casting, so that the corrosion resistance of the casting is improved. The method has such advantages as simple operation, short treatment time, high production efficiency, low energy consumption and obtaining of the cast iron casting with high corrosion resistance.

Description

technical field [0001] The invention relates to a method for improving the corrosion resistance of cast iron castings, belonging to the technical field of corrosion and wear resistance of metal materials. Background technique [0002] Cast iron with high Cr content is widely used in metallurgy, mining, chemical industry, water conservancy and other fields, but in the actual use process, it is found that such cast iron parts often fail before reaching the expected service life. The reason is Especially in the working conditions of metallurgy, mining, chemical industry, water conservancy, etc., the cast iron with high Cr content not only has a huge wear consumption, but also is accompanied by various degrees of corrosion damage, and the corrosion damage directly affects the cast iron with high Cr content. The actual wear life of the material. Therefore, under many special working conditions, iron castings with high Cr content are not only required to have good wear resistance...

AI Technical Summary

Problems solved by technology

[0007] The technical problem to be solved in the present invention is: the method for improving the corrosion resistance of cast iron castings with high Cr content has disadvantages such as poor practicability and high risk, and the corrosion resistance of the matrix structure of cast iron castings with high Cr content is low during the corrosion and wear process. Corrosion will accelerate the wear and tear of castings under the coexistence of corrosion and wear

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