ОСОБЛИВОСТІ ФОРМУВАННЯ СТРУКТУРИ КОМПОЗИТІВ СИСТЕМИ сBN-TiC-Al

• Date: 2019
• Main Authors: Беженар, Микола, Романенко, Ярослав, Гарбуз, Тетяна
• Format: Article
• Language: Ukrainian
• Published: Институт сверхтвердых материалов им. В. Н. Бакуля Национальной академии наук Украины 2019
• Subjects: Ключові слова: кубічний нітрид бору; карбід титану; надтвердий композит; високий тиск; рентгеноструктурний аналіз; фазовий склад; твердість.
• Online Access: http://altis-ism.org.ua/index.php/ALTIS/article/view/115
• Journal Title: Tooling materials science

The paper presents the results of the study of the structure and properties of PCBN composites obtained by reaction sintering under high pressure and temperature conditions of the cBN-TiC-Al system. The high-pressure apparatuses of the "anvil with a recess" were used. As a result of structural analysis in the composite, the phases cBN, AlN, TiC and solid TiхAl1-xB2 are identified. No solid-liquid nitrogen and oxygen solutions in the TiC crystal lattice, as well as carbon (graphite), were identified as separate phases. The formation of a solid solution of titanium and aluminium diborides testifies to the reaction interaction on the interphase contacts of TiC-cBN and TiC-Al, as well as the effect of TiC on the inhibition of structural transformations from diboride to higher aluminum borides when changing the thermobaric parameters of sintering. It is noted that during the joint sintering of cBN and TiC powders, the solid-phase interaction between them is realized by diffusion of light elements (oxygen, nitrogen, carbon). This leads to the formation of solid solutions based on the crystalline titanium carbide Ti(C,O) and cubic boron nitride B(N,O) crystalline gratings, while structural vacancies in the sublattices of titanium and boron are formed under heterovalent substitution conditions.