Fatigue and Fracture of Additively Manufactured Metallic Materials

Design of critical load carrying components utilizing additive manufacturing (AM) processes is still at its infancy. This is due to the fact that most of the load carrying components made by AM processes are subjected to cyclic loads, and fatigue behavior of AM metals is far less understood as compared with those made by conventional methods. To better understand the fatigue behavior of AM metals, a wide range of issues that affect the behavior in a synergistic manner must be considered. These include the effects of defects, residual stresses, surface finish, geometry and size, layer orientation, heat treatment, stress concentrations, and stress states. In this article, these features are reviewed and illustrated by reference to data from several AM metals.