New Experimental Results on the Phase Diagram of Boron Nitride

Emissivity of Boron Nitride and Metals for the Solar Probe Plus Mission

“…8). In these characterizations, no change could be identified between the initial state and after treatment at 2200 K. This stability at high temperature, and the absence of phase change, was provided by the stability of boron nitride in the hexagonal form at low pressure and high temperature [16,17]. Besides high-temperature tests, the MEDIASE facility was also used to investigate the behavior of the pBN coating under VUV radiation and proton bombardment at high temperature.…”

Characterization of boron nitride phase transformations in the Li–B–N system under high pressure and high temperature

“…Up to now, the largest size of cBN crystals, obtained by using temperature gradient method, is just a few millimeters [4]. Experimentally, Li 3 N is an appropriate catalyst for cBN growth under high temperature and high pressure (HPHT), and different phase diagrams of BN in the Li-B-N ternary system have been revealed by different authors [5][6][7]. The catalysis principles of Li 3 N for cBN synthesis have been discussed in the previous papers [8][9][10][11][12][13].…”

Cubic boron nitride-containing ceramic matrix composites for cutting tools

“…However, later experiments suggested that the P-T phase boundary could be shifted to lower pressures, where cBN is a thermodynamically stable phase under ambient conditions depending on the purity of the binders, the initial structure of the material and sintering parameters (time, temperature, pressure, etc.). 20,22,23 Shulzhenko et al observed that cBN dispersion affects the cBN-hBN phase transformation in cBN-Al composites. 20 With better dispersion of the cBN powder, the peaks in the cBN-hBN transformation curve shift to lower temperatures, while the addition of aluminum cause it to shift to higher temperatures.…”

“…The most probable mechanism for rBN formation is a cooperative crystal-oriented reconstruction of the cBN structure, while the subsequent rBN-hBN transformation was a reconstructive one, possible under the conditions where diffusion processes became active. Hu et al 23.1 P-T phase diagram of boron nitride (solid line, refi ned diagram; dashed lines, Solozhenko's diagram). Solid squares show Wentorf's data 1 on hBN melting.…”