【摘要】 以Ni-42Mo-28Si和Ni-36Mo-24Si(质量分数计)合金粉末为原料,利用激光熔敷技术在1Cr18Ni9Ti不锈钢基材表面制得由三元金属硅化物Mo2Ni3Si初生树枝晶和枝晶间Mo2Ni3Si/NiSi共晶组织组成的复合材料涂层,考察了涂层镍含量及Mo2Ni3Si初生相体积分数对涂层在滑动干摩擦下的耐磨性的影响.结果表明:激光熔敷Mo2Ni3Si/NiSi金属硅化物复合材料涂层在滑动干摩擦条件下具有优异的抗磨性能;随着涂层中三元金属硅化物Mo2Ni3Si初生相体积分数的增加,涂层的耐磨性提高,摩擦系数降低;激光熔敷Mo2Ni3Si/NiSi金属硅化物复合材料涂层具有良好的载荷特性.更多还原

【Abstract】 Mo2Ni3Si/NiSi wearresistant metal silicide composite coatings were fabricated on 1Cr18Ni9Ti austenitic stainless steel substrate by laser cladding, using NiMoSi elemental powder blends as the raw materials. The microstructure of the resulting composite coating and its worn surface morphology were analyzed by means of optical microscopy and scanning electron microscopy. The phase compositions of the composite coating was examined by means of Xray diffraction and energy dispersive spectrometry. The friction and wear behavior of the composite coating sliding against quenched and tempered AISI1045 steel at ambient condition was evaluated on an MM200 friction and wear tester. Results indicated that the laser clad Mo2Ni3Si/NiSi metal silicide composite coatings had fine microstructure consisting of Mo2Ni3Si primary dendrites and the interdendritic Mo2Ni3Si/NiSi eutectics. The composite coatings had excellent dry sliding wear resistance which was improved with increasing volume fraction of the primary ternary metal silicide Mo2Ni3Si. Moreover, the wear mass loss of the laser clad Mo2Ni3Si/NiSi metal silicide composite coating was much insensitive to increasing applied load.更多还原