LOW-OXYGEN-PURIFIED STEEL AND LOW-OXYGEN-PURIFIED STEEL PRODUCT

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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 mm2, and contain Al2O3 and REM oxide are dispersed in the steel, an average proportion of the Al2O3 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.