Shot Peening Quality Research for Structure Parts Made by 15-5PH Steel

Poor harshness, color difference and turnup of sharp edge areas were found after structure parts of 15-5PH steel were shot peened. After analysis and test verification, it is found that the harshness of the parts after shot peening is not directly related to the shot peening intensity, but it is affected by shot peening parameters, including air pressure, flow and angle of shot peening. The harshness after shot peening decreased with the decrease of air pressure, but increased with the decrease of flow. When the shot peening angle is 90¦, the best harshness can be obtained. In order to avoid the color difference and turnup after shot peening, the installation equipment should be improved to ensure the whole surface for shot peening will be exposed, and the shot peening surface should avoid repeated clamping and overlapping area. In addition, the shot peening parameters should be improved. For sharp edge areas of the parts, the shot peening intensity should be small to reduce the impact of balls on sharp tips, and the shot peening path should be adjusted to decrease the impact time of balls on sharp tips.