To provide a rail in which the generation of pro-eutectoid cementite in a rail columnar part, further, a head part and a foot part, is restrained and the development of brittle fracture and the lowering of fatigue strength and toughness, is prevented and the wear resistance of the rail head part is secured in a high carbon steel rail.
In the steel rail containing 0.90-1.20 mass% C, after hot-rolling into the rail-shape, the foot tip part of the rail is acceleratively cooled to at least 650°C at 5-20°C/sec cooling velocity from the austenite (γ) zone temperature within 60 sec, and/or the columnar part is acceleratively cooled to at least 650°C at 2-20°C/sec cooling velocity from the γ zone temperature within 100 sec. As the other way, within 60 sec after hot-rolling into the rail-shape, the temperature at the foot tip part is elevated by 50-100°C from the temperature before the temperature rise and/or within 150 sec, the temperature of the columnar part is elevated by 20-100°C from the temperature before the temperature rise. Then, the head part and the foot part are acceleratively cooled to at least 650°C at 1-10°C/sec cooling velocity from the γ zone temperature.
MATSUSHITA KOICHIRO
FUJITA KAZUO
Tomoyuki Yabuki