利用X射线应力测定仪,显微硬度计,白光共聚焦显微镜,SEM等微观分析手段,分析了国外滚动直线导轨副的导轨未跑合区、加减速区、匀速区以及滑块的上下滚道的残余应力、显微硬度、金相组织的分布,并对比了国内滚动直线导轨副的导轨匀速区的残余应力、显微硬度、金相组织的分布.结果表明,导轨上滚道的淬硬层深度大于下滚道的淬硬层深度,淬硬层深度越深,滚道表面残余应力越小,滚道面磨损会导致残余应力增大.导轨加减速区摩擦产生热量导致滚道的淬火热影响区深度增加,硬化区和过渡区的金相组织发生变化.原始组织中铬元素分布的不均匀性,导致成品导轨副基体金相组织中存在较为明显的带状组织,同时导轨淬硬区金相组织中板条状马氏体和针状马氏体的分布也影响导轨副的疲劳寿命.%Using X-ray stress tester, microhardness tester, white light confocal microscope, SEM micro-scopic analysis methods,analyze the distribution of residual stress,microhardness gradient and metallurgical structure of the upper and lower raceway surface of not-running area,the acceleration and deceleration area and uniform area of linear guide of foreign production, compare the distribution of residual stress, micro-hardness gradient and metallurgical structure of raceway surface of uniform area of linear guide of domestic production. The results show that the depth of hardened layer on the upper raceway is larger than the depth of the hardened layer of the lower raceway,the depth of hardened layer is deeper,the residual stress is smal-ler,the wear of raceway surface will increase the residual stress. Heat generated by the friction of the accel-eration and deceleration area of guide lead to the increase of depth of quenched heat affected zone of the raceway,the microstructure of the hardened zone and the transition zone changes. Inhomogeneity of chromi-um distribution in original tissues lead to obvious banded structure in the microstructure of the substrate, at the same time,the distribution of lath martensite and acicular martensite in the microstructure of the harden-ed zone of the guide rail also affects the fatigue life of the guide.
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