LOW-OXYGEN CLEAN STEEL AND LOW-OXYGEN CLEAN STEEL PRODUCT

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A low-oxygen-purified steel contains C, Si, Mn, P and S as chemical components, and also contains, in mass%, 0.005 to 0.20% of Al, more than 0% and 0.0005% or less of Ca, 0.00005 to 0.0004% of a REM, and more than 0% and 0.003% or less of T.O. In the steel, the content of the REM, the content of Ca and the content of T.O satisfy the requirements represented by the formulae : 0.15 = REM/Ca = 4.00 and Ca/T.O = 0.50; non-metal inclusions are dispersed in the steel, wherein the non-metal inclusions have the maximum predicted diameter of 1 to 30 µm inclusive as measured by a method based on extreme value statistics under the conditions in which the predicted area is 30000 mm2, and contain Al2O3 and a REM oxide; the average content of Al2O3 in the non-metal inclusions is more than 50%; and the REM is at least one rare earth element selected from La, Ce, Pr and Nd. The steel is an Al deoxidized steel or an Al-Si deoxidized steel.