Summary: | This paper studies the multiaxial fatigue behaviour of maraging steel samples produced by selective laser melting. Hollow cylindrical specimens with transverse circular holes are subjected to different in-phase bending-torsion loading scenarios. Fatigue crack initiation sites and fatigue crack angles are predicted from the first principal stress field. Fatigue lifetime is computed using a straightforward approach, based on a one-parameter damage law, developed via uniaxial low-cycle fatigue tests. The cyclic plasticity at the notch-controlled process zone is accounted for by combining the equivalent strain energy density concept and the theory of critical distances within a linear-elastic framework. Regardless of the multiaxial loading scenario, experimental observations and predicted lives are very well correlated.
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