The low-cycle tension–tension fatigue properties of extruded Mg–3Al–1%Zn alloy plate have significantly different features in twinning-dominated samples and dislocation-dominated samples. The twinning-dominated samples exhibited more pronounced cyclic hardening and longer fatigue lives than those of the slip-dominated samples. The elongated lifetime of the twinning-dominated samples may have been due to roughness-induced crack closure.

Role of Twinning and Slip in Cyclic Deformation of Extruded Mg-3%Al-1%Zn Alloys. Y.J.Wu, R.Zhu, J.T.Wang, W.Q.Ji: Scripta Materialia, 2010, 63[11], 1077-80