Metallurgical process

Claim 1

PROCESS FOR THE PRODUCTION OF AN IRON-CHROMIUM MASTER ALLOY USEFUL IN THE PRODUCTION FINISHED STEEL FROM INDIVIDUAL ORES INCLUDING (I) A LOW-GRADE CHROMITE ORE, AND (II) AN IRON OXIDE-BEARING ORE, THAT COMPRISES BLENDING SAID INDIVIDUAL ORES IN RESPECTIVE PROPORTIONS TO PROVIDE A MIXED OXIDIC REDUCTION BURDEN CONTAINING IRON AND CHROMIUM IN APPROXIMATE PROPORTION EQUIVALENT TO THE IRON-CHROMIUM CONTENT DESIRED IN SAID FINISHED STEEL FLUXING SAID MIXED REDUCTION BURDEN AND THEREAFTER SUBJECTING THE SAME TO REDUCTION SMELTING WITHIN AN ELECTRIC FURNANCE IN THE PRESENCE OF A CARBONACEOUS REDUCING AGENT IN AN AMOUNT SUFFICIENT TO EFFECT REDUCTION TO THE METALLIC STATE OF SUBSTANTIALLY ALL OF THE IRON OXIDE CONTAINED THEREIN AND AN AMOUNT OF CHROMIUM OXIDE IN EXCESS OF THE CHROMIUM CONTENT DESIRED IN SAID FINISHED STEEL WITH THE PRODUCTION OF A CRUDE MOLTEN IRON-CHORMIUM ALLOY AND A RESIDUAL MOLTEN SLAG PRODUCT, SUBJECTING SAID CRUDE MOLTEN IRON-CHROMIUM ALLOY TO A FIRST OXIDATION TREATMENT WITH A FREE-OXYGEN-CONTAINING GAS IN THE PRESENCE OF A COVERING LAYER OF SAID MOLTEN SLAG OF SUFFICIENT VOLUME TO RETAIN CHROMIUM VALUES OXIDIZED THEREINTO FROM SAID CRUDE ALLOY, THEREBY EFFECTING PARTIAL DECARBURIZATION AND DESILICONIZATION OF SAID CRUDE ALLOY WITH THE PRODUCTION OF A MOLTEN SLAY PRODUCT CONTAINING EXCESS CHROMIUM VALUES OXIDIZED OUT OF SAID CRUDE IRON-CHROMIUM ALLOY UNDER MEDIATE IRON-CHOROMIUM ALLOY OF REDUCED MEDIATE IRON-CHROMIUM ALLOY OF REDUCED CARBON, CHROMIUM, AND SILICON CONTENTS CONTAINING IRON AND CHROMIUM IN APPROXIMATE PROPORTIONS CORRESPONDING TO THE ALLOY COMPOSITION DESIRED IN SAID FINISHED STEEL, AND RECYCLING SAID CHROMIUM OXIDE CONTAINING SLAG TO THE REDUCTION SMELTING FURNACE, SAID INTERMEDIATE ALLOY BEING DIRECTLY REFINABLE TO PROVIDE SAID FINISHED STEEL BY MEANS OF A SECOND OXIDATION TREATMENT, A DEOXIDATION TREATMENT UTILIZING NON-CARBONACEOUS REDUCTANTS, AND NECESSARY ALLOYING ADJUSTMENTS.