W6Mo5Cr4V2高速钢WC/Co激光熔覆表面的摩擦磨损性能

Tribological Properties of High Speed Steel Surface with WC/Co Laser Cladding Layer

为了改善高速钢表面的摩擦磨损性能,应用激光熔覆技术在W6Mo5Cr4V2高速钢表面制备出WC/Co熔覆道。采用三维数码显微镜观察熔覆试件的金相组织并借助显微硬度计测试其显微硬度。采用销盘式摩擦磨损试验机分别对高速钢和WC/Co熔覆试件进行了摩擦磨损试验,并采用三维数码显微镜观察磨损形貌。结果表明:与高速钢基材相比,WC/Co熔覆道硬度提高,熔覆试件的摩擦系数和磨损量降低;WC/Co熔覆道的磨损机制以磨粒磨损为主,熔覆道间隔以磨粒磨损和黏着磨损为主;熔覆道的硬度提高、减摩效果、散热作用以及试件表面熔覆道与间隔面的软硬交替,有助于提高WC/Co熔覆试件的摩擦磨损性能。

WC/Co cladding tracks on W6Mo5Cr4V2 high speed steel specimen surface were fabricated with laser cladding technology to im- prove the tribological properties of high speed steel. The microstructures of specimens were observed by metallurgical microscope, and the hard- ness was measured by microhardness tester. Moreover, the friction and wear tests were carried out by pin- disk tribometer on the high speed steel and WC/CO cladding layer specimens, and the wear morphology was observed by three-dimensional digital microscope. Results showed that compared with high speed steel substrate, the hardness of WC/Co cladding tracks increased. The wear mechanism of WC/Co cladding tracks was abrasive wear, while the wear mechanism of WC/Co cladding track space area included abrasive wear and adhesive wear. In addition, the hardness improvement, friction reduction and heat dissipation of cladding tracks and the hard ＆ soft alternation between cladding tracks and interval surfaces on specimen surfaces were contributed to the improvement of tribological resistance of WC/Co cladding specimens.