Abstract:The surface of GH3535 superalloy was shot peened with shot peening pressures of 0.3MPa, 0.45MPa and 0.6MPa respectively. The optical profiler and scanning electron microscope (SEM) were used to observe the surface profile morphology of the alloy and the structure of the strengthening layer. Through metallographic microscope (OM), Vickers hardness tester, X-ray stress analyzer, the surface grain size, surface microhardness, surface residual stress distribution and X-ray diffraction peak half-height width are analyzed. The high-cycle fatigue experiment was carried out at room temperature, and the morphological characteristics of the fracture were observed and analyzed by means of scanning electron microscope (SEM). The results show that the grain refinement layer, hardened layer and residual compressive stress layer are formed on the surface of GH3535 alloy after shot peening. And the thickness of the grain refinement layer, the thickness of the hardened layer and the thickness of the residual compressive stress layer produced on the surface of the alloy all increase with the increase of the shot peening pressure.The shot peening pressure is in the range of 0.3MPa to 0.6MPa, and the fatigue life is more sensitive to the impact of shot peening pressure, and the fatigue life increases with the increase of shot peening pressure.When the shot peening pressure is 0.6MPa, the effect of shot peening is the best, and the fatigue life is increased by 471.1%.The increase in fatigue life of GH3535 alloy after shot peening benefited from the improvement of the alloy surface condition.