The principle of shot peening and blasting similarity: small nodular or ball with certain hardness by pressure of air or other gas pressure fast jet to parts of the surface, if it is metal, surface deformation of the impact will cause a certain depth and until the surface layer hardened before termination of continued deformation. At the same time, the pressure will cause the corresponding prestress, the prestressing can make component produces dangerous tensile stress in use. But after shot peening, the surface layer hardened indeed has the very high strength and strong wear resistance and corrosion resistance.