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系统研究了２０ＣｒＮｉ２ＭｏＡ渗碳钢铁路轴承精磨时，由于砂轮、工件与冷却液之间的热－化学与热－机械作用，滚道面的成分与组织变化。结果表明，轴承滚道面形成了磨削变质层。变质层由表至里是由吸附层、氧化层、白层及过回火塑性变形层组成。氧化层是Ｆｅ与合金元素氧化物组成的混合结构，并存在Ｓｉ的表面富集。氧化层厚度不超过２０ｎｍ。白层的组织为细化了的高碳织构马氏体与沿磨削切应力方向拉长了的细小的奥氏体。在过回火层中，硬度低于６００ＨＫ的区域不超过１０μｍ。变质层的总厚度及白层厚度均随砂轮径向进给速度增加而加厚。
Systemically studied 20CrNi2MoA carburizing steel railway bearing grinding, due to the wheel, the workpiece and the coolant between the thermal - chemical and thermal - mechanical effects, raceway surface composition and organizational changes. The results show that the bearing raceway surface grinding deformation layer. Metamorphic layer from the table is by the adsorption layer, oxide layer, white layer and over the plastic deformation layer backfire composition. The oxide layer is a mixed structure of Fe and alloying element oxides, and the surface of Si is enriched. Oxide thickness does not exceed 20nm. The white layer is organized into finely textured high-carbon textured martensite and fine austenite elongated along the direction of grinding shear stress. In the tempering layer, the hardness of less than 600HK area does not exceed 10μm. The total thickness of the metamorphic layer and the thickness of the white layer are thickened as the radial feed rate of the grinding wheel increases.