| 摘要 |
<p>PURPOSE: A high hardness heat treated rail using cooling conditions and a method for manufacturing the same are provided to obtain high hardness of a heat treated rail through two-stage cooling speed control. CONSTITUTION: A method for manufacturing a high hardness heat treated rail comprises the steps of: heating a rail material(310) and cooling the heated rail material(320,330). The rail material comprises carbon of 0.79-0.82 weight%, silicon of 0.2-0.4 weight%, manganese of 0.4-0.6 weight%, phosphorus of 0.02 weight% or less, sulfur of 0.02 weight% or less, copper of 0.15 weight% or less, nickel of 0.25 weight% or less, chrome of 0.3 weight% or less, molybdenum of 0.06 weight% or less, vanadium of 0.01 weight% or less, aluminum of 0.01 weight% or less, nitrogen of 0.008weight% or less, oxygen of 0.002 weight% or less, and iron and inevitable impurities of the remaining amount. The heat treated rail has a surface hardness of 390(Hv) or greater.</p> |
