Single crystal elasticity and equation of state of tantalum up to 54 GPa

Abstract

We measured single crystal elasticity of Ta under high pressures up to 54 GPa at room temperature using inelastic x-ray scattering at room temperature. Simultaneously, we measured the density of Ta using x-ray diffraction. Combining the bulk modulus and density, we obtain an equation of state of Ta as a primary scale. The Vinet equation was fitted to the pressure-volume data and we found consistency with previous work including experimental static and shock compressions and theoretical calculation. We proposed a parameter set for the Vinet equation [K0 = 191.1(3) GPa, K′0 = 4.006(2)] which is consistent with the pressure based on extrapolated velocities within 2% up to ∼80 GPa. Furthermore, we found the present scale to be consistent with a recent ruby scale (Ruby2020) up to ∼50 GPa.