Light spot size adjusting method and device for pulse laser shock peening

The invention provides a light spot size adjusting method for pulse laser shock peening, which comprises the following steps of: S110, detecting surface characteristics of a target peening region of ato-be-machined part, and determining a range of a surface curvature value Ki of the target peening region; S120, determining a light spot size P corresponding to the surface curvature value Ki in therange by combining reachable technical indexes of a pulse laser; and S130, acquiring a surface curvature value Ki of a moving path when the target peening region of the to-be-machined part is acted on in real time, and adjusting the light spot size P according to the surface curvature value Ki to continue to carry out shock peening. According to the invention, by detecting the surface characteristics of the peening region of the to-be-machined part and adjusting the light spot size according to the surface curvature, the uniformity of pressure shock waves of surfaces with different curvatures, and the laser shock peen