激光技术, 2012, 36 (5): 627, 网络出版: 2012-09-24
激光熔覆原位生长VC-WxC颗粒增强镍基涂层研究
Investigation on in-situ synthesis of VC-WxC particulate reinforced Ni-based coatings by laser cladding
激光技术 原位生长VC-WxC 激光熔覆 显微组织 硬度 耐磨性 laser technique in-situ synthesized VC-WxC laser cladding microstructure hardness wear resistance
摘要
为了提高45#钢表面强度和耐磨性, 采用激光熔覆技术制备原位生长VC-WxC颗粒增强镍基涂层。使用金相显微镜、扫描电镜、电子能谱和X射线衍射仪对熔覆层显微组织和物相进行了分析, 并对熔覆层显微硬度及摩擦性能进行了测试。在适当工艺条件下, 熔覆层成形良好, 涂层与基体呈现良好的冶金结合; 熔覆层底部组织为定向生长的γ(NiFe)树枝晶, 熔覆层中上部组织为VC,W2C,WC和Cr3C2相, 均匀分布于γ(NiFe)树枝晶基体中; 熔覆层具有极高的硬度(平均HV0.31400), 耐磨性是纯Ni60涂层的6倍。结果表明, 其硬度和耐磨性的提高归因于涂层中大量的VC,W2C,WC和Cr3C2相的生成, 并均匀分布于涂层的基体中。
Abstract
The VC-WxC particulate reinforced Ni-based coating was successfully in-situ synthesized by laser cladding on steel 45# substrates. The micro-structural and metallographic analyses were performed with a scanning electron microscopy, energy-dispersive spectrometer and X-ray diffractometer. The microhardness and wear-resistance of the coatings were investigated. It is indicated that a good finish VC-WxC reinforced composite coating can be reached at a suitable processing parameters. The microstructure at the bottom of the cladding layer mainly consists of oriented dendrites of γ(NiFe), and the microstructure at the center and upper zones contains VC,W2C,WC and Cr3C2 phase dispersed in the matrix of γ(NiFe) solid solution. The in-situ synthesized VC-WxC reinforced Ni-based coating gives very high hardness of HV0.31400 and excellent wear resistance, which is six times as that of Ni60 coatings. The results show that the improvement in hardness and wear resistance of the layer is due to the in-situ synthesis of VC, W2C, WC and Cr3C2 ,its homogenous distribution in the clad layer.
杨宁, 李立凯, 晁明举. 激光熔覆原位生长VC-WxC颗粒增强镍基涂层研究[J]. 激光技术, 2012, 36(5): 627. YANG Ning, LI Li-kai, CHAO Ming-ju. Investigation on in-situ synthesis of VC-WxC particulate reinforced Ni-based coatings by laser cladding[J]. Laser Technology, 2012, 36(5): 627.