STUDY OF VISUAL INSPECTION AND CONTROL METHODS OF EFFECTIVENESS OF LASER SHOCK-PROCESSING

Visual inspection and control methods for the effectiveness of laser s hock-processing (LSP) are described first. The surface qualities of LS P areas can be controlled by adjusting the laser parameters and proces s details by which the difficult technical problems in LSP engineering applications are also solved. The effects of LSP can be evaluated acc ording to surface qualities after LSP, which are quantitatively charac terized by three parameters: surface roughness, hollow depth and surfa ce residual stress. The best surface qualities of the samples are achi eved when the surface roughness is one to two grades less than or equa l to those of an unprocessed area, a very bright shallow hollow is for med and the hollow depth is 6-18 mu m, and high surface residual stres ses are produced in the LP area. Only under these conditions can the b est LSP effect or fatigue life increment be obtained. The LSP effect c an be controlled effectively be means of controlling the surface quali ties of LSP zones. The three different control methods are presented a nd analysed.