Effects of Blasting Parameters on Removability of Residual Grit

A carbon steel was blasted by white alumina, and removability of residual grit was investigated. Blasting parameters such as grit particle size were varied. Residual grit was removed from substrate surface by dissolving the substrate in mixed acid solution, and the amount of residual grit was measured. Removal of residual grit was carried out by ultrasonic cleaning. The amount of residual grit was 7-17 g/m², and penetration depth of embedded grit of most residual grit was 25-40 µm. The amount of residual grit increased with decreasing the grit size. However, the minimum amount of the substrate dissolution required for the grit removal increased with increasing the grit size.