中文摘要：

采用扫描电子显微镜（SEM）、显微硬度仪和能量色散谱仪（EDS）分别对经激光固溶处理后的17-4PH材料强化层的显微组织、显微硬度及元素含量进行了分析.结果表明：激光固溶时效后,17-4PH材料的表层平均显微硬度比基体提高了约40%,接近420 HV0.2;表层存在高密度的位错马氏体组织,且马氏体组织中含有Cr、Ni及Cu等合金元素;激光固溶层的耐磨损性能及抗气蚀性能都有一定程度的提高.根据阿伦尼乌斯定律以及菲克第二定律分析了激光固溶的机理,证明：Cu在激光作用下可以在短时间内完全溶入奥氏体,完成固溶过程.

英文摘要：

Microstructure,microhardness and element content of the strengthened layer of material 17-4PH treated by laser solid solution were analyzed by scanning electronic microscope（SEM）,microhardness tester and energy disperse spectroscopy（EDS） respectively.Results show that after laser solid solution and aging treatment,average surface microhardness of the treated material,compared with the substrate,has been improved by about 40%,approaching to 420 HV0.2;dense dislocated martensite can be found in the surface layer including alloy elements such as Cr,Ni,Cu and so on,of which the wear resistance and anti-cavitation property are both improved to some degree.Mechanism of laser solid solution has been analyzed on the basis of Arrhenius law and Fick＇s second law,indicating that a solid solution process can be finished within a short time by laser,during which Cu will completely dissolve in the austenite.