Effect of pressure on the structural properties of tantalum carbide

Abstract

In this study, tantalum carbide (TaC) samples were placed in a diamond anvil cell to study the equation of state at room temperature and high pressure using synchrotron radiation X-ray diffraction. By fitting the data at ambient pressure and up to the highest pressure of 38.5[Formula: see text]GPa, we obtained the bulk modulus and first derivative of TaC as [Formula: see text] (6.8) GPa and [Formula: see text] (0.49), respectively. In addition, we calculated the bulk modulus and band structure of TaC under high pressure using density functional theory. The obtained bulk modulus is 267 (3)[Formula: see text]GPa. TaC is metallic in nature throughout the entire pressure range. We studied the high-pressure deviatoric stress of TaC using linewidth analysis method. We found that TaC can support a maximum differential stress of up to 18.6[Formula: see text]GPa at the highest pressure of 38.5[Formula: see text]GPa.