采用2 kW 连续波Nd:YAG固体激光器在AA6061铝合金表面激光熔覆Si3N4陶瓷粉末，从而制备出Si3N4颗粒增强金属基复合材料(MMC)表面改性层。利用扫描电子显微镜(SEM/EDX)，X射线衍射(XRD)仪等对改性层的组织形貌、结构及化学成分进行分析。采用恒电位仪及超声波感应空泡腐蚀设备对MMC改性层的电化学腐蚀及空泡腐蚀性能进行了评价，并总结出其空泡腐蚀机制。

Laser surface cladding of Si 3N 4 powder layer on AA6061 aluminum alloy was carried out using a 2 kW CW Nd YAG laser. Subsequent laser surface melting of the layers gave a surface metal matrix composite (MMC). The microstructure and phase identification of the modified layer were examined using scanning electron microscopy (SEM) and X ray diffractometry (XRD) respectively. Cavitation erosion and electrochemical corrosion tests were also performed in 3.5% NaCl solution at 23℃. Finally the cavitation erosion mechanisms of the laser surface cladding modified layers were studied by surface morphology analysis.