Manufacturing method null of the bainitic steel rail which is superior in resistance surface damage

摘要

PURPOSE: To prevent the occurrence of rolling fatigue damage at the surface of a railhead and to prolong the service life of a rail for rapid transit railway. ;CONSTITUTION: A steel, which has a composition containing 0.15-0.45% C, 0.15-1.00% Si, 0.20-2.00% Mn, and 0.20-2.00% Cr and containing, besides the above, one or ≥2 elements among Mo, Cu, Ni, Ti, V, Nb, and B, if necessary, is used. The bainitic steel rail excellent in surface damage resistance can be obtained by subjecting the railhead, after the completion of hot rolling or after heating up to a high temp. for the purpose of heat treatment, to accelerated cooling through the region between the austenite region temp. and the ordinary temp. at a rate of (1 to 10)°C/sec. The resulting rail has superior surface damage resistance as compared with the conventional rails, and the service life of the rail can be remarkably improved.;COPYRIGHT: (C)1994,JPO