The density of stainless steel shot is higher than that of cast steel shot and wire cut shot. Therefore, at the same size and shot blasting speed, it has higher kinetic energy to impact the workpiece surface, can better press out pits to introduce residual compressive stress, play the role of gear surface stress strengthening, while improving the gear surface hardness and wear resistance; secondly, stainless steel shot has less dust, is not easy to break, is impact-resistant, and has strong anti-rust ability, is environmentally friendly and low-carbon, and the gears treated with it are cleaner.