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① High-quality die steel raw materials are used for smelting in the intermediate frequency furnace.

When smelting steel is used for smelting, high-quality raw materials should be selected as much as possible. The content of S and P in scrap steel should be low, and other harmful elements As, Sn, Pb and Cu should be strictly controlled. Scrap should use as much scrap as possible (preferably the return material of this group), or high-quality pig iron. When smelting by the oxidation method, the amount of carbon removal during the oxidation period should be ensured as much as possible.

② High-quality refractory materials are used for smelting in the intermediate frequency furnace.

When smelting tool steel with induction furnace, high-quality refractory refractory materials should be selected. For example, high-quality magnesia-carbon bricks can be used for the lining of the furnace, and high-aluminum or magnesia-carbon bricks are generally used for the ladle, including refractory materials for pouring, etc., which must be paid attention to.