摘要 |
A process is disclosed for the decarburization of a molten bath of chromium-containing pig iron which, in a single operation, permits decarburization by means of an oxygen jet and thus permits chromium or nickel chromium steels to be obtained directly, the decarburization of which can readily be completed by a final treatment under vacuum carried out immediately after the injection of oxygen. The process comprises adjusting the temperature conditions of the pig iron bath and regulating the oxygen jet distance from the surface of the bath and speed of oxygen gas so that the impact force of the oxygen creates a gas-metal emulsion within which the carbon contained in the pig iron is oxidized directly by the oxygen. The carbon content is thus rapidly reduced to less than 0.3% whereas the yield of chromium is higher than 97%. The process is suitable for the preparation of all grades of Cr and NiCr stainless steel, which optionally contain additions of Co, Mn or Mo. |