Evolution, Control, and Mitigation of Residual Stresses in Additively Manufactured Metallic Materials: A Review

Powder bed fusion (PBF) and directed energy deposition (DED) are the two major types of metal additive manufacturing (AM) processes, in which significant residual stresses could be generated in the as-deposited materials and in turn affect part quality and performance. Therefore, how to control and mitigate residual stress has been a most pressing challenge for metal AM. Herein, the significant efforts made in literature to address this challenge for both PBF and DED processes are reviewed. The extensive survey covers the formation of residual stress in AM, influence of various AM process parameters, modeling techniques for predicting residual stresses, and post and in situ treatments for mitigating unfavorable residual stress distributions. More importantly, a critical analysis is provided to discuss the research gaps and opportunities, such that more exciting research will be stimulated to address the outstanding issues in this area and improve the quality and service life of AM-produced components. As a result, once being better equipped with residual stress control knowledge and tools, the industry will be more confident in adopting metal AM techniques.