Shock response of single crystal rhenium: Effect of crystallographic orientation

Rhenium, a unique engineering material with the second highest melting point of all metals, has significant application potential in harsh service environments, and thus evaluating its mechanical responses under shock loadings is of great importance. Through molecular dynamic simulations, we have systematically investigated the effect of crystallographic orientations on the mechanical responses of single crystalline rhenium under shock compression. We have obtained the P–V/V_0, U_p-P, P-T, and U_s-U_p Hugoniot relations, and evaluated their anisotropies. The particle velocity, P_zz, and shear stress show orientation dependent when tracing the shock profiles at different time, and the difference is particularly pronounced for shear stress, resulting from the atomic arrangement in the HCP crystal structure of rhenium. The plastic deformations mechanisms of rhenium single crystal under shock loadings are revealed as the emission of dislocations and the generation of disordered atoms, and the influence of shock intensity on the plastic deformation mechanism has been systematically studied. The results presented in this work not only shed light on the effect of crystallographic orientations on the mechanical responses of monocrystalline rhenium under shock compression, but also offers fundamental insights for understanding the shock induced plastic deformation mechanisms, which could provide a valuable supplement to the investigations of mechanical properties pertaining to rhenium.