大型铁路轴承表面变质层研究

Studies on the Surface Affected Layersin Huge Railway Bearing

应用显微硬度、光学显微镜、X射线衍射、SEM及 AES等,分析与研究了大型铁路轴承(197 726)表面变质层的成分、组织与残余应力,发现变质层中硬度的变化与磨削热产生的相变及表层碳量下降有关,表面存在很大残余压应力,但分布不均匀。

The structures, compositions and residual stresses of the surfaceaffected layers in huge railway bearing (197 726) have been analysed andinvestigated by microhardness, optical microscopy, x--ray diffraction (XRD),scanning electron microscopy (SEM), and Auger electron spectroscopy (AES).It was found that the microhardness changes in affected layers is related tothe phase transformations which are caused by grinding heating and carboncontent reduction in the surface layers. The large residual compression stressesis found in the surface, but the distribution is non--uniform.