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Plasma smelting refers to a type of metallurgical method that uses inert gas (such as argon), reducing gas (such as hydrogen) or a mixture of two gases as a medium, and a pure plasma arc or plasma beam with a temperature of more than 30,000 degrees as a heat source for smelting. The general term. It can be smelted in a lining furnace, or it can be melted and purified in the form of consumable electrodes. Mainly used in the production of special steel, ultra-low carbon stainless steel, high-temperature alloys, and reactive and refractory metals (such as tungsten, molybdenum, rhenium, tantalum, niobium, zirconium, etc.).