METHOD FOR SMELTING TITANIUM-CONTAINING STEEL

摘要

PURPOSE:To improve the yield of Ti at the time of producing the Ti-contg. steel and to control the Ti content to a target grade with high accuracy by suppressing the content of SiO2 in molten slag at the time of producing the Ti-contg. steel to a specific value or below and controlling the contents of N and Ti in the molten steel tapped into a ladle to a specific quantitative relation. CONSTITUTION:The slag of a high content of the SiO2 sticking to a refining furnace and ladle at the previous refining of the molten steel is previously removed at the time of refining the Ti-contg. steel in an electric furnace. The Si content of the crude molten steel to be charged to the refining furnace is simultaneously adjusted to =0.3% and a slag making agent which is suppressed in SiO2 content as far as possible is used as the slag forming agent to be used at the time of the refining. Al is used without using Si for deoxidation of the molten steel in the refining furnace. The SiO2 content in the molten slag at the time of the tapping is suppressed to =3% and the quantitative relation expressed by equation I is maintained between the N content (ppm) and Ti content (%) of the molten steel received in the ladle after the refining by the above-mentioned method, by which the Ti-contg. steel having the target Ti grade is stably produced at the high Ti yield.