Elastic moduli and hardness of c-Zr2.86(N0.88O0.12)4 having Th3P4-type structure

Abstract

The equation of state of the recently discovered oxygen-bearing cubic zirconium (IV) nitride, c-Zr2.86(N0.88O0.12)4, was measured at room temperature in a diamond anvil cell using x-ray powder diffraction combined with synchrotron radiation. From these studies the bulk modulus B0=219(13)GPa and its first pressure derivative B0′=4.4(1.0) [or B0=223(5)GPa, for B0′ fixed at 4] were obtained. Applying nanoindentation techniques the reduced modulus Er≈220GPa and hardness H≈18GPa were measured for porous c-Zr2.86(N0.88O0.12)4. The shear modulus of c-Zr2.86(N0.88O0.12)4 was estimated to be at least G0=96(13)GPa using the experimental data of B0 and Er, exclusively.