Abstract
We have investigated the effect of beryllium additions on the kinetics of conversion of hexagonal graphite-like BN to cubic BN (hBN → cBN) as well as on the linear rate of cBN crystal growth in a Li-B-N (H, Be) system. Experiments were performed in the temperature range 1940-2080K at a pressure of 4.3GPa. With the addition of 0.25 and 0.50wt.% beryllium the activation energy of the cBN formation process is found to be 45.8 and 42.0kJ/mol, respectively. The resulting crystals showed p-type conductivity. The activation energy of the impurity carriers for the samples with 0.25 and 0.50 wt.% beryllium additions equalled 0.22 and 0.17eV, respectively.
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