Patent ID: 8404178
Filing Date: 2013-03-26
Classification: C21D,C22C

Abstract:
1. A pearlitic steel rail having a composition consisting of, in mass percent, 0.6 to 1.0% of C, 0.1 to 1.5% of Si, 0.4 to 2.0% of Mn, 0.035% or less of P, 0.0005 to 0.010% of S, optionally 0.004% or less of O, optionally 0.001 to 0.01% of Ca, optionally one or more elements selected from the group consisting of 0.5% or less of V, 1.5% or less of Cr, 1.0% or less of Cu, 1.0% or less of Ni, 0.05% or less of Nb, 1.0% or less of Mo, and 1.0% or less of W, no more than 2 ppm hydrogen, and the remainder being Fe and inevitable impurities, wherein the tensile strength is 1200 MPa or more, and the size of a long side of an A type inclusion is 250 μm or less in at least a cross-section in a longitudinal direction of a rail head, and the number of A type inclusions, each having a size of a long side of 1 to 250 μm, is less than 25 per observed area of 1 mm