轧后不同冷却方式下U76CrRE重轨钢的摩擦磨损性能

以不同冷却方式下的U76CrRE重轨钢为研究对象，采用摩擦磨损试验机、SEM(扫描电镜)、EDX(能谱仪)、CLSM(激光共聚焦显微镜)等测试分析了钢轨在水摩擦、干摩擦、沙摩擦3种条件下的摩擦因数、磨损量、微观组织及磨损面的合金元素成分。结果表明，在相同的磨损时间下，风冷试样的平均摩擦因数比空冷试样的小，且在沙摩擦情况下，风冷试样的磨损量远小于空冷试样；风冷试样经水摩擦后存在少量划痕，出现剥落坑，为分层磨损，干摩擦下存在犁痕，同时在犁脊上出现横裂纹，为氧化磨损，沙摩擦下出现大量的沙粒和磨屑，磨损的最严重，属于磨粒磨损，且空冷试样表面磨痕平整，犁沟更为明显；风冷试样的变形层均小于空冷试样，而且沙摩擦的变形层最大。风冷条件下的U76CrRE重轨钢比空冷条件下具有更好的耐磨性。

Friction and wear performance of U76CrRE heavy rail steel under different post-rolling cooling modes

Taking U76CrRE heavy rail steel under different post-rolling cooling modes as the research object, the friction factor, wear amount, microstructure and wear-surface alloy element composition of the rail under water friction, dry friction and sand friction were analyzed by means of friction and wear tester, SEM (scanning electron microscope), EDX (energy dispersive spectrometer) and CLSM (laser confocal microscope). The results show that under same wear time, the average friction coefficient of air-blast-cooled specimen is smaller than that of air-cooled specimen, and the wear amount of air-blast-cooled specimen is much less than that of air-cooled specimen under sand friction. For the air-blast-cooled specimen, a small amount of scratches and peeling are formed after water friction, which are delamination wear; there are plough marks under dry friction and transverse cracks on the plough ridge, which are oxidized wear; and under sand friction, a large amount of wear debris appears and the most serious wear is abrasive wear. And the surface of the air-cooled specimen is flat and the pear groove is more obvious. The deformation layers of the air-blast-cooled specimens are all smaller than that of the air-cooled specimen, and the sand friction deformation layer is the largest. The U76CrRE heavy rail steel under air-blast-cooling has better wear resistance than that under air cooling.