激光熔覆Fe/NiCr-Cr3C2复合涂层的组织和磨损性能

利用激光熔覆技术在GCr15 钢表面制备Fe/NiCr-Cr₃C₂复合涂层,研究不同NiCr-Cr₃C₂含量对铁基涂层微观组织和磨损性能的影响。结果表明:随NiCr-Cr₃C₂含量的增多,复合涂层显微组织逐渐细化,在铁基合金里掺入NiCr-Cr₃C₂金属陶瓷粉末导致复合涂层里残留奥氏体含量增多,α-Fe相含量减少,截面硬度显著降低。当加入10%NiCr-Cr₃C₂时,复合涂层中出现较多的Cr₃C₂和Cr₂₃C₆硬质相,同时磨痕表面生成了具有减摩作用的氧化产物,从而降低了磨耗和摩擦阻力,使涂层表现出最佳的耐磨性能。

Microstructure and wear resistance of laser clad Fe/NiCr-Cr3C2 composite coating

Fe/NiCr-Cr₃C₂ composite coating was prepared on GCr15 steel surface by laser cladding, and the effect of NiCr-Cr₃C₂ on microstructure and wear resistance of the composite coating was investigated. The results indicate that the microstructure of the composite coating refines gradually with the increase of NiCr-Cr₃C₂ content from 0 to 20%. With addition of NiCr-Cr₃C₂ into the Fe-base alloy, the residual austenite content increases in the composite coating, while the α-Fe phase content decreases, resulting in the decrease of cross-section microhardness. The composite coating added with 10% NiCr-Cr₃C₂ exhibits optimal wear resistance, and reduces the wear loss and friction resistance, which can be attributed to the formation of many hard carbide phases (Cr₃C₂ and Cr₂₃C₆) and oxide lubricating phase during wear process.