LOW-ALLOY HEAT-TREATED PEARLITIC STEEL RAIL EXCELLENT IN WEAR RESISTANCE AND WELDABILITY AND PROCESS FOR PRODUCING THE SAME

摘要

The present invention relates to a pearlitic steelrail having the significantly improved wear resistance andweldability (welding construction, properties of thewelded joints) that rails for heavy load are required tohave, and a process for producing the same. The presentinvention particularly relates to a pearlitic steel railexcellent in wear resistance and weldability, comprising,in terms of weight, more than 0.85 to 1.20 of C, 0.10 to1.00% of Si, 0.20 to 1.50% of Mn, more than 0.50 to 1.00%of Cr, or comprising more than 0.85 to 1.20% of C, 0.40 to1.00% of Si, 0.20 to less than 0.40% of Mn, 0.35 to 0.50%of Cr, the content sum Si/4 + Mn/2 + Cr being 0.80 to0.95% or being 0.8 to 1.8% in terms of weight, furthercomprising, in terms of weight, one or at least twoelements selected from the group consisting of Mo, V, Nband B and the balance Fe and unavoidable impurities, andhaving a pearlite structure to the depth of at least 20 mmfrom the head portion corner and the head top surface as astarting point, the pearlite structure having a Vickershardness of at least 320, the difference in Vickershardness between the base steel and the welded joint ofthe steel rail being made up to 30 to prevent a wear dentcaused by the local wear of the rail top surface in thewelded joint without impairing the weldability.