Investigation on post processing techniques oriented towards strength improvement of 3D printed SS316L

Additive manufacturing has its roots in all manufacturing sectors, right from conventional lathe tool to nose plate of rockets. Additive manufactured components provide better strength than cast products but have lower strength than forged components. 3D printed components always require post processing to improve the strength. Strength can be enhanced by heating, followed by modified cooling techniques. At some points, electron beam and laser source increase the strength of the component. Shot blasting and shot peening improve the fatigue life of the component. This study focuses on the post processing of 3D printed Stainless Steel (SS) 316L material. Various parameters involved in 3D printing of SS316L have an influence on the final product. SS316L material finds its application in automotive and aerospace industries with different property requirements. Subsequent to 3D printing, post processing is also very important to meet the required mechanical and physical properties. Post processing includes laser peening technique to improve the strength as observed during mechanical testing that includes hardness and residual stresses analysis. Metallurgical study that includes microscopy, FESEM with EDS mapping shows the change in microstructural arrangement which contributes to the improvement in strength. Surface profile as observed in the final product, has higher value compared to that of the as-built specimens.