超音速火焰喷涂Cr3C2-NiCr涂层的显微组织与磨损性能

Microstructure and Wear Properties of High Velocity Oxygen Fuel Sprayed Cr3C2-NiCr Coating

采用超音速火焰喷涂技术在H13钢基体上制备Cr3C2-NiCr涂层,研究了涂层的显微组织、物相组成及摩擦磨损性能,并探讨了磨损机理。结果表明:Cr3C2-NiCr涂层与H13钢基体结合紧密,厚度约为340μm;涂层由Cr3C2硬质相、NiCr黏结相及少量Cr7C3相组成,组织致密,孔隙率为0.63%;Cr3C2-NiCr涂层与H13钢的稳定摩擦因数分别为0.90,0.75,涂层磨痕深度及磨损率仅为H13钢的1/2,涂层耐磨性能较好;Cr3C2-NiCr涂层的磨损机理主要为磨粒磨损和疲劳磨损。

The Cr3C2-NiCr coating was prepared on H13steel substrate by high velocity oxygen fuel spraying technique.The microstructure,phase composition and friction and wear properties of the coating were studied,and the wear mechanism was discussed.The results show that the Cr3C2-NiCr coating with a thickness of about 340μm was closely combined with the H13steel substrate.The coating was composed of Cr3C2hard phase,NiCr bonding phase and a small amount of Cr7C3,and the structure was dense with a porosity of 0.63%.The stable friction coefficients of the Cr3C2-NiCr coating and H13steel were 0.90and 0.75,respectively,and the wear track depth and wear rate of the coating were only half that of H13steel,showing that the coating had relatively good wear resistance.The main wear mechanism of the Cr3C2-NiCr coating was abrasive wear and fatigue wear.