A computational study of plasticity induced damage during Surface Mechanical Attrition Treatment (SMAT) in TWIP/TRIP AISI 304 stainless steel
Abstract
Surface Mechanical Attrition Treatment (SMAT) is a mechanical surface treatment process that generates higher level of compressive residual stress coupled with stronger plastic deformation in the near surface region of structures than conventional shot peening. SMAT is based on multidirectional mechanical impacts between balls and the surface of material. The particularity of this technique lies in the fact that it can transform the top surface layer of material from coarse grains to nano-sized grains due to severe plastic slips. The over-treatment during surface mechanical treatments such as shot peening can generate damage in the near surface region. A good understanding of deformation mechanisms of material during SMAT, including damage, is important in terms of material processing optimization.