| 摘要 |
<p>PURPOSE:To decrease harmful nonmetallic inclusions and to produce the steel for springs having excellent fatigue characteristics by subjecting a high-carbon steel adequately adjusted in the relation between Mn/Si and total Al content in a molten steel to a molten steel treatment by using Ca-SiO2 slag. CONSTITUTION:The molten high-carbon steel of 0.5 to 1% C adjusted in such a manner that the relation between the ratio Mn/Si of the Mn and Si in molten steel components and the total content of Al attains the adequate range shown in Fig. is subjected to the molten steel treatment by using the CaO-Si deg.C2 slag. The molten steel is preferably continuously cast under electromagnetic stirring in a casting mold after the above-mentioned molten steel treatment. The purpose for using the CaO-SiO2 slag at the time of the above-mentioned molten steel treatment is to accelerate the absorptivity of Al2O3 system inclusions. The harmful nonmetallic inclusions are decreased in this way and the steel for springs most adequate for valve springs for automobiles, etc., is obtd.</p> |
