Multiaxial low cycle fatigue behavior and life prediction of wire arc additive manufactured 308L stainless steel.

• Multiaxial low cycle fatigue behaviors of 308L SS fabricated by WAAM and hot-rolling technology are studied comparatively. • WAAM 308L SS exhibits significant non-proportional additional hardening phenomenon similar to the hot-rolled material. • Under uniaxial loading, WAAM 308L SS has longer fatigue life under high strain amplitudes. • Under torsional loading, WAAM 308L SS exhibits a significantly shorter fatigue life under each strain amplitude. • The CXH model can predict the fatigue life of both hot-rolled and WAAM 308L SS over a range of loading conditions. Wire arc additive manufacturing (WAAM) is a technique that has gained popularity in various industrial sectors due to its high productivity and flexibility. However, the comprehension of cyclic deformation and fatigue behaviors in WAAM austenitic stainless steel (SS), particularly under complex multiaxial loading conditions, is much less advanced compared to conventional manufacturing methods. This study aims to fill some of these gaps by performing fatigue tests of WAAM 308L SS under axial, torsional and axial–torsional multiaxial loadings. Similar tests were carried out on the hot-rolled 308L SS as a basis for comparison. WAAM 308L SS exhibits notable distinctions in cyclic deformation, fatigue life, cracking mode and fatigue failure mechanisms compared to its hot-rolled counterparts as a result of its distinct manufacturing technologies and resulting microstructures. To assess all fatigue life data, three critical plane criteria, namely FS, SWT and CXH criteria, were employed. The CXH model, which considers the effects of both tensile and shear damage on fatigue properties, has the ability to predict the fatigue life of both hot-rolled and WAAM 308L SS. [ABSTRACT FROM AUTHOR]