Investigating the residual stress in additive manufacturing of combined process in powder bed fusion and directed energy deposition

Abstract

Residual stress is the secondary stress that still exists even after removing all loads. Parts manufactured by directed energy deposition on powder bed fusion contain residual stress, which can be compressive or tensile. When performing directed energy deposition processing on a powder bed fusion substrate, if these residual stresses are not considered, it may cause stress fatigue cracks, deformation, corrosion cracks, design examples, and premature component failure. Residual stress calculation is very important for deformation analysis, life prediction, and evaluation of failure causes. The purpose of this study is to understand the residual stress evaluation of powder bed fusion substrate additives made of stainless steel 316L powder in directed energy deposition treatment. In order to evaluate the residual stress value in additive manufacturing, the value can be obtained by X-ray diffraction technique.