N. N. Belyavina

X-ray diffraction analysis of aluminum nitride sintered with cubic boron nitride

Abstract X-ray diffraction spectra of AIN after HP-HT sintering of a mixture containing AIN and c-BN have been examined. A residual elastic strain in the AIN lattice was found in the samples after the pressure was removed. It is envidenced by the decrease in both the lattice constant ratio ( c a ) and the unit cell volume. Such a state of the lattice is typical of AIN at 8 GPa. For analysis of experimental results, a calculation was made of the thermoelastic strain caused by the difference in elastic moduli and thermal expansion coefficients of c-BN and AIN. The residual change in the c a ratio and the unit cell volume in the AIN lattice after the pressure is removed is shown to be due to two factors: thermoelastic deformations in the phases of the composite and physico-chemical interactions between the components of the charge.

Special features of the crystal structure of titanium diboride that forms in superhard composites of the cBN-Al-TiB2 system

Special Features of the Crystal Structure of Titanium Diboride that Forms in Superhard Composites of the cBN–Al–TiB2 System N. P. Bezhenara, S. A. Bozhkoa, T. A. Garbuza, N. N. Belyavinab, and V. Ya. Markivb aBakul Institute for Superhard Materials, National Academy of Sciences of Ukraine, ul. Avtozavodskaya 2, Kiev, 04074 Ukraine bTaras Shevchenko Kiev National University, ul. Volodymyrs’ka 64, Kiev, 01033 Ukraine