Orientation-dependent responses of tungsten single crystal under shock compression via molecular dynamics simulations

Abstract

The orientation-dependent mechanical responses of shock loading on tungsten single crystal are investigated via molecular dynamics simulations. All the simulated Hugoniot relations are comparable with the available experimental data. By linear fitting our us–up data, we produced the relation us=(3.975±0.207)+(1.331±0.113)up, which compare relatively well with the experimental results. Combined Hugoniot P–T curve and radial distribution function (RDF), we detected that the solid–liquid transition occurs at the (P, T) points of (311GPa, 9166K)–(335GPa, 9938K) along [100], (295GPa, 7762K)–(321GPa, 8590K) along [110], and (211GPa, 5396K)–(237GPa, 5972K) along [111] orientation. The shock profiles, i.e. unshocked, shock front and post shocked regions, are investigated in detail by tracing the evolutions of stresses, particle velocities, temperatures, local-order parameters and RDFs from one- or two-dimensional. Moreover, the time-dependent stresses profiles are also further analyzed.