Mechanical properties of superhard boron subnitride B13N2

Abstract

Microstructure and mechanical properties of bulk polycrystalline rhombohedral boron sub-nitride B₁₃N₂ synthesized by crystallization from the B–BN melt at 7 GPa have been systematically studied by micro- and nanoindentation, atomic force microscopy and scanning electron microscopy. The obtained data on hardness, elastic properties and fracture toughness clearly indicate that B₁₃N₂ belongs to a family of superhard phases and can be considered as a promising superabrasive or binder for cubic boron nitride.