Rail having excellent resistance to rolling fatigue damage and rail having excellent toughness and wear resistance and method of manufacturing the same

摘要

A high-abrasion bainite rail excellent in resistance to rolling fatigue and failure, consisting essentially of 0.15 to 0.55 wt. % of C, 0. 05 to 1.0 wt. % of Si, 0.1 to 2.5 wt. % of Mn, 0.03 wt. % or less of P, 0. 03 wt. % or less of S, 0.1 to 3.0 wt. % of Cr, 0.005 to 2. 05 wt. % of Mo, and the balance being iron and inevitable impurities. The head portion of the rail has a uniform bainite structure. The Vickers hardness at any position of the head top portion and the head corner portion is 240 to 400 Hv. A rail of high toughness and high wear resistance, consisting essentially of 0.2 to 0.5 wt. % of C, 0.1 to 2.0 wt. % of Si, 1.0 to 3.0 wt. % of Mn, 0.035 wt. % or less of P, 0.035 wt. % or less of S, 0.3 to 4. 0 wt. % of Cr, and the balance being iron and inevitable impurities. The rail has a bainite structure, a hardness of greater than 400 Hv at each of a head top portion and a head corner portion thereof, both the head top portion and the head corner portion having a substantially uniform hardness at all sections thereof. The rail having a tensile strength of 1200 MPa or more, and a 2 mm, U-notch Charpy absorbed energy of 30 J or more at +20° C.