Review of shot peening processes to obtain nanocrystalline surfaces in metal alloys

The importance of application of shot peening process to obtain nanocrystal surface is presented with an inclusive clarification of actual state of the art. Description of different shot peening methods which have proved to be able to create nanocrystallised layers is presented. Then the available microstructural characteristics of nanocrystal thin layers obtained with different processes are depicted. In addition, the influence of the process is reviewed on material behaviour under different loading conditions. On this basis, some possible addresses for future research in this field are drawn and underlined.