激光熔覆层对轮轨滚动接触疲劳磨损性能的影响

Effects of Laser Cladding Layers on Wheel/Rail Rolling Contact Fatigue Wear Performance

在高速轮轨钢表面制备添加钇稳定纳米氧化锆的超声振动辅助的激光熔覆铁钴复合基涂层。通过扫描电镜、X射线衍射仪和显微硬度仪等分析了熔覆层的微观组织、物相组成和显微硬度;采用GPM-30轮轨接触疲劳实验机研究了添加钇稳定纳米氧化锆前后的激光熔覆层的滚动接触疲劳磨损性能。结果表明:通过激光熔覆可获得优质的熔覆层,添加了钇稳定纳米氧化锆的熔覆层的磨损状况得到改善。添加3.5%的钇稳定纳米氧化锆的强化效果最佳,与不添加任何合金粉末的熔覆层相比,磨损速率分别降低56.5%、61.6%。

Fe-Co-based composite coatings with yttria-stabilized nano-zirconia by ultrasonic vibration assisted laser cladding was prepared on high-speed wheel/rail steel.The microstructure,phase composition and microhardness of the cladding layer was analyzed by SEM,XRD and microhardness tester.The rolling contact fatigue wear properties of the laser cladding layer before and after the addition of yttria-stabilized nano-zirconia were compared using GPM-30 wheel-rail contact fatigue tester.The results show that the high quality cladding coating can be obtained by laser cladding.The wear condition of the cladding layer with yttrium-stabilized nano-zirconia improves.The addition of 3.5%yttrium-stabilized nano-zirconia has the best strengthening effect,and the wear rate reduces by 56.5%and 61.6%,respectively,compared with the cladding layer without adding any alloy powders.