PROCESS FOR PREVENTION OF NITROGEN ABSORPTION DURING TAPPING OF EXTREME LOW-CARBON, LOW-NITROGEN STEEL

摘要

PURPOSE: Provided is a high quality of low-carbon, low-nitrogen steel by adjusting a slag basicity in a refining furnace and adding a fluorite to prevent nitrogen absorption from atmosphere. CONSTITUTION: The process prevents nitrogen absorption from atmosphere by adjusting the slag basicity into 2.2-2.6 during decarboxylation or reducing carbonate in refining process, and adding the fluorite of 14-17% to the input of total burnt lime, so it can be useful to minimize the nitrogen content in smelting furnace which seriously deteriorate a corrosion resistance and a tenacity of molding part.