通过化学沉积法制备了Ni-Mo-P/Ni-P梯度合金镀层。采用XRD定量分析、SEM/EDS扫描电镜观察及光学干涉法,并通过显微硬度测试、摩擦磨损试验,研究了退火前后梯度合金的晶化组织特征、硬度、耐磨性及磨损机理。结果表明,从镀态到300℃退火后,梯度合金外层Ni-Mo-P仅发生Ni相晶化,内层Ni-P还伴有Ni3P析出。从400℃到800℃退火后,外层开始发生Ni3P晶化反应,同时Ni-Mo固溶体形成,800℃晶化程度约为97.13%,而内层完全晶化。无论内层还是外层,在Ni3P刚开始析出时,Ni相的晶粒尺寸总是小于Ni3P相。梯度合金400℃热处理后的显微硬度出现峰值,但相应的耐磨性最低;600℃热处理后表现出优异的耐磨性,这一性能特征可为在高温条件下工作、且要求保持高耐磨性的工件的工业应用提供潜在的可能性。梯度合金的磨损机制主要取决于外层磨屑中含有的Ni/Ni-Mo、Ni3P相尺寸大小对内层摩擦磨损过程的影响以及内层的组织状态。 Ni-Mo-P / Ni-P gradient alloy coatings were prepared by chemical deposition. The microstructure, hardness, wear resistance and wear mechanism of the gradient alloy before and after annealing were studied by means of XRD, SEM / EDS scanning electron microscopy and optical interferometry. The microhardness and frictional wear tests were carried out. The results show that Ni-Mo-P in the outer layer of the gradient alloy only undergoes Ni phase crystallization and Ni-P in the inner layer also precipitates after annealed from 300 ℃. After the annealing from 400 ℃ to 800 ℃, the outer layer began to crystallize Ni3P and the Ni-Mo solid solution formed, the degree of crystallization at 800 ℃ was about 97.13%, while the inner layer was completely crystallized. Regardless of the inner or outer layer, the grain size of the Ni phase is always less than the Ni3P phase at the onset of the Ni3P precipitation. The microhardness of the gradient alloy after heat treatment at 400 ° C shows the peak value, but the corresponding wear resistance is the lowest. After 600 ° C heat treatment, it shows excellent wear resistance. This property can be characterized as working under high temperature and requiring high resistance Industrial applications of abrasive workpieces offer potential possibilities. The wear mechanism of the gradient alloy mainly depends on the influence of Ni / Ni-Mo and Ni3P phase size on the friction and wear of the inner layer and the microstructure of the inner layer.