Pearlite steel rail of high internal hardness type excellent in wear resistance and fatigue failure resistance and process for production of the same

Abstract

The invention provides a pearlite steel rail of high internal hardness type which is excellent in both wear resistance and fatigue failure resistance and a process suitable for the production of the rail. Specifically, a pearlite steel rail which has a composition containing by mass C: 0.73 to 0.85%, Si: 0.5 to 0.75%, Mn: 0.3 to 1.0%, P: 0.035% or below, S: 0.0005 to 0.012% and Cr: 0.2 to 1.3% with the balance consisting of Fe and unavoidable impurities and having a [%Mn] / [%Cr] ratio of 0.3 or above and below 1.0 (wherein [%Mn] is Mn content and [%Cr] is Cr content) and whose railhead exhibits an internal hardness of Hv380 or above and below Hv480 in terms of Vickers hardness (Hv)in a depth range of at least 25mm from the railhead surface.

Description

technical field

[0001] The present invention relates to an internal high hardness type pearlitic rail excellent in wear resistance and rolling contact fatigue (RCF) resistance and a manufacturing method thereof, specifically, It relates to the realization of the long life of the track used under severe high-axle load conditions, such as overseas mining railways with heavy weight of freight cars and many high curve lines (longer operating life) internal high-hardness pearlitic steel rail excellent in wear resistance and fatigue damage resistance and a manufacturing method thereof. Background technique

[0002] On the high-axle load railway (high-axle load railway) mainly transporting ore (mineral ore), the load imposed on the axle (axle) of the truck is much larger than that of the passenger car (passenger car), and the use environment of the rails (use environment) also become harsh. Rails used in such an environment have conventionally used steel mainly having a pearlite ...

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