Influence of Surface Mechanical Attrition Treatment (SMAT) on Microstructure, Tensile and Low-Cycle Fatigue Behavior of Additively Manufactured Stainless Steel 316L

Direct Energy Deposition (DED), as one common type of additive manufacturing, is capable fabricating metallic components close to net-shape with complex geometry. Surface mechanical attrition treatment (SMAT) an advanced surface technology which able yield a nanostructured layer characterized by compressive residual stresses and work hardening, thereby improving the fatigue performances specimens. In present study, stainless steel 316L specimens were fabricated DED subsequently treated SMAT. Both uniaxial tensile tests tension-compression low-cycle conducted for as-built SMAT processed The microstructure both conditions was roughness hardness measurements, scanning electron microscopy transmission microscopy. After SMAT, nanocrystallites microtwins found in top layer. These microstructural features contribute superior properties surfaces. Finally, it can be concluded that performance additively manufactured under static loading improved process.