This method can level uneven metal surfaces and deburr sharp edges. In addition, it can create shiny surfaces ranging from semi-gloss to chrome like.
For shot peening small abrasive particles are hurled at high speed against the surface to be treated, either by centrifugal wheel, compressed air, or jet injector systems. The abrasive impact is accelerated and brought onto the surface by high speed and high air pressure (up to 10 bar, typically 2 to 5 bar). This leads to a hardening and an elastic-plastic deformation in the surface resulting in residual compressive stress of the workpiece.
In shot peening the aspect of residual compressive stress to increase the fatigue strength of the material is most important. Increased corrosion resistance and surface area make shot peening a widespread method and are essential e. g. in bonding components.
A major drawback of this method is a weakening of the component caused by mishandling (e. g. too much pressure, too little distance to the blasting medium). A shorter and/or reduced fatigue strength and bending strength of the workpiece are possible consequences.