Elastic-plastic coupled α→ω phase transformation of zirconium under shock loading: experiments and non-hydrostatic thermodynamic-based modeling

Modeling the martensitic transformation of solid materials under shock loading is still an unsolved problem. One of the key challenges is the effect of shear stress and elastoplastic coupling on the dynamic response. In this paper, we perform a specific shock experiment in which zirconium samples with three different microstructures and mesostructures are prepared using a rolling process and their dynamic responses are measured under completely consistent loading conditions to investigate the effects of shear stress and elastoplastic coupling on the pure zirconium α→ω phase transformation. The results clearly show that the phase transformation of the three samples is completed along different elastoplastic coupling paths, and the dynamic response characteristics of the phase transformation are completely different. To the best of our knowledge, such contrast data have not been reported in previous experimental results. Subsequently, a theoretical model based on non-hydrostatic thermodynamics and considering the effects of elastoplastic coupling was proposed, and then numerical simulations were carried out. The results indicate that the proposed model can effectively simulate experimental measurements.