Application of Shot Blasting on Bronze Alloy to Enhance Surface Integrity

Shot blasting enhances the fatigue strength of the components as well as improves the surface finish and hence finds major applications in industries. Hence, in this work, bronze alloy is subjected to shot blasting to improve the tribological properties of the interacting surfaces. The surfaces of normal tin bronze, shot blasted tin bronze and shot blasted tin bronze with molybdenum coating were observed under metallurgical microscope model L-2003A and compared. It is observed that the effect of shot blasting on the deterioration of surface-roughness on grounded surface of molybdenum coating is more than the normal tin bronze. Rate of wear on the specimens which have undergone shot blasting was found to be lesser than the normal ones due to the presence of surface work-hardened layer and elimination of tensile stresses that try to stretch or pull the surface apart with induction of compressive residual stress by shot blasting. The molybdenum coated tin bronze has improved strength and resistance to wear than normal shot blasted ones. The cavities, holes and dendrites were very less in molybdenum-coated, shot blasted tin bronze when compared with the other two specimens, which ensures the significance of the shot blasting.