On twinning in ultrahard nanocrystalline cubic boron nitride

Abstract

International audienceMicrostructure of bulk nanocristalline cubic boron nitride synthesized at 20 GPa and 1770 K has been studied by scanning and high-resolution transmission electron microscopy. The material is characterized by high density of twins with average size of 5.5 nm, and multiple stacking faults within the twin domains that results in the exceptional material hardness