| 摘要 |
PROBLEM TO BE SOLVED: To provide a high internal hardness type pearlitic steel rail which is excellent in both of wear resistance and fatigue deterioration resistance, by increasing hardness in a range of 25 mm deep from the surface of a railhead, and also to provide a preferable method for manufacturing the same. SOLUTION: This pearlitic steel rail has a composition comprising, 0.73-0.85 mass% C, 0.5-0.75 mass% Si, 0.3-1.0 mass% Mn, 0.035 mass% or less P, 0.0005-0.012 mass% S, more than 0.5 mass% and equal to or less than 1.3 mass% Cr and the balance Fe with unavoidable impurities, while a value of [%Mn]/[%Cr] is controlled to 0.3 or more but less than 1.0, in which [%Mn] represents an Mn content and [%Cr] represents an Cr content. The railhead contains more than 0.20 mass% and equal to or less than 0.50 mass% precipitated Cr, and has an internal hardness of Hv 395 or more but less than Hv 480, which is defined by Vickers hardness in a range of at least 25 mm deep from the surface of the railhead. COPYRIGHT: (C)2010,JPO&INPIT |
