Structural special features and infrared spectra of absorption of ultradisperse boron nitride

The dimensional factor effect on the structural features and infrared absorption spectra of ultradisperse powders of highly anisotropic boron nitride in a wide range of powder grain size was examined. X-ray diffraction revealed extensive turbostratic deformation of the crystal structure. The powder was subjected to vacuum heat treatment and annealing in a closed molybdenum crucible. The ultradisperse powders showed marked anisotropic deformation of the crystal lattice. The interatomic bonds were found to shorten within the limits of the flat lattices and the crystal lattice strain was removed from the ultradisperse boron nitride during vacuum heat treatment accompanied by sintering.