Effect of spherical inclusions on fatigue anisotropy of HSLA-100 steel

Abstract

The fatigue limit of the transverse direction was obtained remarkably (125 MPa) lower than that of the longitudinal direction. The fatigue anisotropy was related to different characteristics of inclusions on longitudinal and transverse planes as well as the crystallographic texture. These parameters change the fatigue crack initiation mode from the metal matrix to spherical inclusions. Exaggeratedly conservative results were obtained utilising the Murakami's model in predicting the lower bound fatigue limit and largest size of inclusion.