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Metallurgy refers to the process and process of extracting metals or metal compounds from minerals and making metals into metal materials with certain properties by various processing methods. Metallurgy has a long history of development, from the Stone Age to the subsequent Bronze Age, and then to the large-scale development of modern steel smelting. The history of human development is fused with the history of metallurgy.

Due to the harsh working conditions of petroleum underground, many downhole tools bear the load for a long time and are used in the working conditions of corrosion and wear, resulting in premature failure and failure, and thus shortening their life. For example: oil plunger, large rotor journal, sleeve, bearing bush, oil drill collar, wear plate, wear band, etc., but these parts are often very expensive.