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Information × Registration Number 0225U000863, (0122U000404) , R & D reports Title Study of the mechanisms of structure formation of composites based on cubic boron nitride (cBN) under conditions of high pressures and temperatures using the methods of pre-hot pressing (PRB) and direct conversion sintering popup.stage_title Вивчення механізмів структуроутворення композитів на основі кубічного нітриду бору (cBN) в умовах високих тисків і температур з використанням методів попереднього гарячого пресування (КНБ) та прямого конверсійного спікання Head Turkevych Volodymyr Z., Доктор хімічних наук Registration Date 20-01-2025 Organization V.N.Bakul Institute for Superhard Materials of the National Academy of Sciences of Ukraine popup.description1 Substantiation of the possibility of obtaining superhard composite materials for instrumental purposes of group BL based on cubic boron nitride (cBN), which is formed by thermobaric conversion sintering of precursors of graphite-like modification (hBN) used in a mixture with carbides, nitrides and carbonitrides of transition metals Ti, Nb, W). popup.description2  Thermobaric sintering was used to obtain superhard multicomponent composites based on cBN of the BL group with the phase composition cBN-TiC-TiCN-TiB2 and cBN-TiC-TiSi2-TiCN-TiB2. The instrumental PcBN (for which the Young's modulus and shear modulus are 881 and 395 GPa, respectively, and the Vickers hardness is 63.4 GPa) has been produced using hBN precursor. New composites with a specific heterophase vortex structure have been obtained using hBN precursor together with TiN and TiCN (∼55 vol. % cBN). The specific wear of such a cBN-TiCN composite during diamond grinding is not inferior to the BH group composite (BSN, 97 % cBN). Instrumental PcBN composites of BL group have been produced by means of reactive two-stage sintering under high pressure. They contain 45-50% cBN by volume, TiCN bonds, and they have less than 2 μm phase dispersion and a structure strengthened by the products of TiB2 and AlN interaction. The composites have Knoop hardness of 27 GPa, Vickers hardness of 35 GPa, and a crack resistance of 11 MPa⸱m0.5. PcBN composites of the cBN-Al, cBN-TiC, cBN-TiN, cBN-TiCN, cBN-Co systems were obtained. BL composites of cBN-TiC-Al, cBN-TiN-Al, cBN-TiCN-Al systems performed no worse than the analogue plates produced by Element Six, when processing hardened ХВГ steel with a hardness of 59 - 62 HRC (in smooth turning mode at a cutting speed of 200 m/min). The best results were shown by the cutting tool made of PcBN, which was obtained from the initial powder with a phase composition of 87% cBN-13% AlN. Product Description popup.authors Biliavyna Nadiia М. Bezhenar Mykola P. Bushlya Volodymyr M. Hazha Heorhii P. Harhin Vladyslav H. Hriaziev Oleksandr V. Devin Leonid M. Zaporozhets Oleh I. Leschuk Oleksandr O. Melah Lyudmila M Melniichuk Yurii O. Mykhailovskyi Vladyslav A. Moshchil Viktor Ye. Nikolenko Andrii S. Nechyporenko Volodymyr M. Osipov Oleksandr S. Patsyk Andrii M. Petrov Ihor V. Petrusha Ihor A. Romanenko Yaroslav M. Rumiantseva Yuliia Yu. Rusinova Nataliia O. Sadovyi Petro S. Smirnova Tamara I. Sokolov Oleksandr M Staryk Serhii P. Stasiuk Liubomyr P. Stratiichuk Denys A. Trokhanchuk Vasyl V. Fedak Fedir V. Shokina Liudmyla P. Shulzhenko Alla O. popup.nrat_date 2025-01-20 Close