Molecular dynamics studies of body-centered cubic tungsten during melting under pressure

摘要

Highlights?A pressure-dependent embedded-atom-method potential for tungsten is introduced.?The melting curves of tungsten is consistent well with experimental data.?Radial distribution functionsg(r) of tungsten are studied during melting.AbstractA pressure-dependent embedded-atom-method (PDEAM) potential for the body-centered cubic (bcc) tungsten (W) is introduced in the pressure range of 0–400?GPa, which makes theP-V/V0curve of bcc W in highly consistent with the experimental data. It is found that all the pressure-dependent parameters for repulsive core-core interaction term (c0,c1,c2,c3,c4andc) increase first and become constants later, while the pressure-dependent parameters for n-body term (Aandd) decrease first before they tend to constants. The reliability of our PDEAM potential is confirmed by studying the lattice constant, elastic constants, cohesive energy, vacancy formation energy, structural stabilities, zero pressure melting point, and the equation of states of the bcc W. With the PDEAM potential, we determined the melting curves, self-diffusion coefficients of liquid W along the melting curve, and entropies of fusion of the bcc W over a wide pressure range. Moreover, we obtained the structural properties of W including the variations of radial distribution functionsg(r) during melting and with increasing pressure.Graphical abstractApplied the pressure-dependent embedded-atom-method potential of W, the calculated melting curves is consistent more well with the experimental data.Display Omitted]]>