THE MAKING METHOD OF HIGH PURITY AL-SI COMPLEX DEOXIDIZING STEEL

摘要

PURPOSE: Provided is a method for manufacturing Al-Si deoxidized steel of high cleanliness degree by using an electric furnace and a ladle furnace. CONSTITUTION: In the manufacture method of Al-Si deoxidized steel comprising the process of (i) adjusting the sum of iron oxide/manganese oxide to 3¯8wt.% and adjusting the sum of calcium oxide/silicon oxide/aluminum oxide to 0.25¯0.45wt.% in electric furnace slag; (ii) adjusting aluminum content and silicone content in the conditioned slag to 0.01¯0.07wt.% and 0.15¯0.35wt.% respectively through reduction of silicon oxide in the conditioned slag, the present method further comprises the process of pouring 2¯9.5kgAl/1tonmolten steel while tapping molten steel from an electric furnace; pouring 20¯65kgelectric furnace slag/1tonmolten steel while receiving molten steel in a ladle; pouring calcium oxide 12¯25kg, calcium carbide 2¯6kg, and 0. 4¯1.2kg of aluminum per 1tonmolten steel on the upper surface of slag for slag conditioning; severe bubbling after pouring 0.3¯1.5kgAl/1tonmolten steel/slag for the purpose of reducing silicon oxide contained in conditioned slag.