| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method of a rail of high toughness, in which the growth of re-crystallized grainγduring and after rolling is suppressed, a pearlite structure of the grain is obtained, and the toughness is provided in the steel representing pearlite structure with high carbon content of excellent strength and wear resistance. SOLUTION: In this manufacturing method of a rail of high wear resistance and toughness representing pearlite metal structure, a steel slab containing, by mass, 0.6-1.20% C and other alloy elements is subjected to rough rolling, and the intermediate rolling is performed by a reverse rolling mill at the surface temperature between 900 and 1,050 deg.C. Next, the finish rolling is performed by a continuous rolling mill at the surface temperature between 850 and 1,000 deg.C with at least two passes of reduction ratio per pass of 5-30% and <=10 seconds between rolling passes. After the rolling, the steel slab is cooled to 800-950 deg.C at the cooling speed of 0.5-50 deg.C/s on the rail surface, and subjected to the natural or accelerated cooling.
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