Long Lifetine heat treatment technique of high-carbon chromium bearing collar

Abstract

This invention relates to surface carbonitriding treatment on high carbon chromium (GCr15) bearing rings, which comprises the steps of: placing the high carbon chromium (GCr15) bearing rings in a thermal treatment furnace (carbon potential and nitrogen potential are 1.0-1.5, 2-6%, respectively), keeping the temperature at 810-830 deg.C for 1.5-3 hrs, quenching and tempering at 150-180 deg.C for 1.5-4 h. This invention can increase the content of the residual austenite in the bearing rings so that the surface exists residual stress, which can significantly extend the service life of the bearings.

Description

technical field

[0001] The invention relates to a bearing surface chemical heat treatment process, in particular to a surface carbonitriding treatment process for a high-carbon chromium (GCr15) bearing ring. Background technique

[0002] Under the condition of the same material, in order to improve the performance, it is generally necessary to carry out surface treatment on the key parts of the product to improve the service life of the entire product. The heat treatment method of the conventional high-carbon chromium (GCr15) bearing ring is to heat it to 820-860 Keep warm at ℃, then quench and temper at 150-180℃ for 1.5-4 hours. According to this heat treatment process, the residual austenite content of the bearing ring is 7-12%, and the surface is in a state of tensile stress. Since the bearing bears a very large load during use, and the working conditions are very bad (such as in an automobile transmission), serious failure of the bearing will occur, resulting in unpredi...