Laser shock peening and its effects and modeling on fatigue performance of additive manufactured metallic materials

Additive Manufacturing (AM) Technology has improved over the decades, and its usage has significantly increased in recent years. However, defects in AM parts have always been a major point of concern. Several postprocessing techniques exist to improve the quality of AM parts, including Laser Shock Peening (LSP) which is gaining attention as an effective technique, although a costly technique. This process induces compressive residual stress in a part, subsequently improving the component's fatigue performance. LSP can also affect surface roughness, hardness, microstructure, and porosity level of fabricated components and, therefore, fatigue performance. This study reviews the effects of LSP as a post-processing technique to improve fatigue performance. In addition, LSP data from the literature are used to model the primary effect of LSP, which is compressive residual stress, in fatigue performance modeling by using several mean stress models.