Prediction of multiaxial fatigue life of notched maraging steel components manufactured by selective laser melting

Abstract

This paper aims at predicting the fatigue crack initiation life in maraging steel manufactured by selective laser melting under in-phase bending-torsion loading. Three relationships between the bending moment and the torsion moment were studied, namely B/T=2, B/T=1, and B/T=2/3. The tested geometries consisted of hollow cylindrical specimens with lateral holes. The crack initiation and the crack paths were detected in-situ using a high-resolution digital camera. The local stress-strain states at the notch region were accounted for using two alternative numerical models developed within linear-elastic frameworks: (1) a parametric structured mesh; and (2) an automatic unstructured mesh. Fatigue crack initiation sites and fatigue crack initiation lives were successfully predicted using both numerical models.