| 摘要 |
Low-oxygen clean steel is provided containing C, Si, Mn, P, and S as chemical components, and further containing, by mass %, 0.005% to 0.20% of Al, greater than 0% to 0.0005% of Ca, 0.00005% to 0.0004% of REM, and greater than 0% to 0.003% of T.O, wherein the REM content, the Ca content, and the T.O content satisfy 0.15‰¤REM/Ca‰¤4.00 and Ca/T.O‰¤0.50, nonmetallic inclusions which have a maximum predicted diameter of 1 µm to 30 µm measured using an extreme value statistical method under the condition in which a prediction area is 30,000 mm 2 , and contain Al 2 O 3 and REM oxide are dispersed in the steel, an average proportion of the Al 2 O 3 in the nonmetallic inclusions is greater than 50%, the REM is one or two or more of rare-earth elements La, Ce, Pr, and Nd, and the steel is Al-deoxidized steel or AI-Si-deoxidized steel. |
