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Traditional magnesium alloy gas protection technology:Since the molten magnesium alloy will burn in the exposed air, it is avoided to contact the air as much as possible. Therefore, when the furnace temperature reaches 350 °C, the protective gas mixer will automatically provide the shielding gas proportionally. The traditional shielding gas adopts SF6 (SO2) and N2, and the distribution relationship of the shielding gas in the furnace is: air, nitrogen, SF6 (SO2) , magnesium liquid.