| 摘要 |
PURPOSE: To produce a highly wear resistant rail excellent in ductility and toughness by refining the grain size of the pearlite block in respectively specified ranges from railhead surface and from railfoot, respectively, in the cross section of a rail having high carbon content and pearlitic structure. CONSTITUTION: A bloom of a steel, containing, by weight, >0.8-1.20% C, 0.10-1.20% Si, and 0.40-1.50% Mn or further containing one or >=2 kinds among 0.05-2.00% Cr, 0.01-0.30% Mo, 0.02-0.10% V, 0.002-0.01% Nb, and 0.1-2.0% Co, is roughed and then hot-rolled at a relatively small rolling reduction of 5-30% in reduction of area, and hot rolling is finished at about 1000 deg.C. The average grain size of the pearlite block in the cross section of a rail is refined so that it is 20-50μm in the range between the railhead surface and a position at a depth of at least 20mm from the railhead surface and in the range between the railfoot and a position at a depth of 15mm from the railfoot and also 35-100μm in the part other than the above. Further, in the former parts, elongation value and U-notch Charpy value are regulated to >=10% and 15J/cm<2> , respectively. By this method, the pearlitic rail, excellent in strength, hardness, ductility, toughness, and wear resistance, can be produced.
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