采用激光修复技术和GH4169合金粉末，在GH738合金基材试块上制备激光成形修复件，对其进行固溶+双时效热处理。对试块进行了高温持久和高温低周疲劳性能试验，观察试样断口形貌并分析断裂机理。结果表明：激光修复GH4169/GH738合金的组织结合处冶金质量良好，呈现向外连续生长的柱状晶组织；在650 ℃、690 MPa下进行持久试验，修复试样晶界析出Laves相，导致裂纹的萌生，与晶界分离形成微观空洞，同时气孔促进了裂纹的扩展，为穿晶和沿晶的混合韧性断裂模式。在455 ℃下进行低周疲劳试验，发现疲劳裂纹源于表面和气孔，以河流状花样向中心扩散，拓展区存在疲劳辉纹，为解理和穿晶两种断裂模式。采用GH4169合金粉末修复可满足常规铸锻GH738合金性能要求。

The laser forming repaired (LFR) and GH4169 superalloy powder were used to prepare laser-formed repair parts on GH738 superalloy substrate specimens, which were subjected to solution + double aging heat treatment. The specimens were subjected to high-temperature endurance and high-temperature low circumference fatigue performance tests, the fracture morphology of the specimens was observed and the fracture mechanism was analyzed. When the persistent test was conducted at 650 ℃ and 690 MPa, the Laves phase was precipitated at the grain boundaries of the repaired specimens, leading to the crack sprouting. This will be separated from the grain boundary to form microscopic cavities, while the gas porosities promote the crack expansion, as a mixed ductile fracture mode of penetration and along with the crystal. Low cycle fatigue test at 455 ℃, the fatigue cracks originated from the surface and gas porosities and spread to the center in a river-like pattern, and there were fatigue glow lines in the expansion area, which were two fracture modes of transgranular and cleavage fracture. The GH4169 superalloy powder repair can meet the conventional casting and forging of GH738 alloy.