INTERNAL HIGH HARDNESS TYPE PEARLITIC RAIL WITH EXCELLENT WEAR RESISTANCE, ROLLING CONTACT FATIGUE RESISTANCE, AND DELAYED FRACTURE PROPERTY AND METHOD FOR PRODUCING SAME

摘要

An internal high hardness type pearlitic rail withexcellent wear resistance, rolling contact fatigueresistance, and delayed fracture properties and a preferredmethod for producing the same are provided. Specifically,the internal high hardness type pearlitic rail has acomposition containing 0.73% to 0.85% by mass C, 0.5% to0.75% by mass Si, 0.3% to 1.0% by mass Mn, 0.035% by mass orless P, 0.0005% to 0.012% by mass S, 0.2% to 1.3% by mass Cr,0.005% to 0.12% by mass V, 0.0015% to 0.0060% by mass N, andthe balance being Fe and incidental impurities, wherein thevalue of [%Mn]/[%Cr] is greater than or equal to 0.3 andless than 1.0, where [%Mn] represents the Mn content, and[%Cr] represents the Cr content, and the value of [%V]/[%N]is in the range of 8.0 to 30.0, where [%V] represents the Vcontent, and [%N] represents the N content, and wherein theinternal hardness of a rail head is defined by the Vickershardness of a portion located from a surface layer of therail head to a depth of at least 25 mm and is greater thanor equal to 380Hv and less than 480Hv.