Abrupt irreversible transformation of rhombohedral BN to a dense form in uniaxial compression of CVD material

• Published in: Diamond and related materials Vol. 8; no. 2; pp. 361 - 363
• Main Authors: Novikov, N.V, Petrusha, I.A, Shvedov, L.K, Polotnyak, S.B, Dub, S.N, Shevchenko, S.A
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-03-1999
• Subjects: BN phases; Cubic boron nitride; In situ; Pressure; Texture; BN phases; Pressure; Texture; In situ; Cubic boron nitride
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/S0925-9635(98)00373-2

The behavior of rhombohedral BN has been investigated under uniaxial compression along the [001]
r texture axis of a highly textured CVD rBN material (thin plate sample) in a diamond anvil cell without a gasket. An abrupt martensitic transformation of the graphite-like rBN structure to a dense cubic BN form accompanied by a distinct acoustic emission signal has been recorded at the sample center at a pressure somewhat above 5.6
GPa, which is an order of magnitude below the threshold pressure of the transformation under hydrostatic compression.