Next steps for an insight on the link between geometrical inclusion characteristics and damage in a shape memory alloy during fatigue loading

The fatigue life and the underlying microstructural fatigue mechanisms are highly sensitive not only on microstructural effects, like grain size or the hierarchical structure characteristics, but also on mesoscopic imperfections, like inclusions or voids. These mesoscopic imperfections are a common measure for the material quality itself as well as the material processing technology. Yet, the quantitative link between such mesoscopic imperfections and the underlying fatigue mechanisms have to be understood in a much more detailed manner for shape memory alloys. Based on priorly conducted studies, a further and more detailed view will gained with respect to the impact of geometrical characteristics of particle void assemblies (PVA) on the development of plastic strains at the very near of the transition area at PVA’s boundaries. These geometrical characteristics include the shape, size, orientation with respect to the global loading direction during fatigue as well as the state of the inclusion itself - bonded, partly debonded, broken or fully debonded and gone (void). Furthermore, the dependency of temperature and strain amplitude on the plastic strains is investigated.