Abstract: Nickel-based single crystal superalloy blades are prone to fatigue and fracture in the high-temperature corrosion working environment during service. The effect of laser shock processing on the thermal corrosion resistance of single crystal alloy with different number of laser shock was studied. The microhardness of the longitudinal section of the alloy before and after laser shock was measured by using the microhardness tester. The microstructures of the surface and longitudinal section of the corrosion layer were observed and analyzed by using the Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS), and the surface phase structure of the corrosion layer was determined by using the X-Ray Diffraction (XRD). The experimental results show that after the alloy was strengthened by laser shock, the surface microhardness and section hardness influence layer depth of the alloy both increase with the increase of the number of laser shock. During the short-term thermal corrosion experiment of the alloy, when the number of laser shock increased to 1, 2, and 3 times, the maximum weight gain per unit area of corroded alloy decreased from the value of alloy without laser shock 2.87 mg·cm^-2 to 2.17, 1.81, 1.10 mg·cm^-2; the corrosion layer depth reduced from 91 μm to 65, 41, 27 μm; the size, depth and number of surface corrosion pits were significantly reduced, and compactness of the protective oxide film was improved. The results show that laser shock processing can effectively improve the thermal corrosion resistance of single crystal alloy under the condition of 900℃/75% Na₂SO₄-25% NaCl salt film.

Key words: laser shock processing, single crystal alloy, short-term thermal corrosion, microhardness, microstructure