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Information × Registration Number 0224U000827, 0123U102772 , R & D reports Title К-I-11 (3013) Development of new superhard composite materials based on cubic boron nitride for working components of cutting tools designed as a new generation popup.stage_title Head Turkevych Volodymyr Z., Доктор хімічних наук Registration Date 12-01-2024 Organization V. Bakul Institute of superhard material of the National Academy of Sciences of Ukraine popup.description2  The materials of composite systems "cBN-NbN-microfibers" with the addition of Al2O3, SiС, Si3N4 microfibers were created. It was established that obtaining such materials under atmospheric pressure is characterized by the formation of a stable hexagonal boron nitride modification in the structure. The addition of Al2O3, SiС microfibers does not cause the formation of solid solutions, chemical compounds and the interaction of microfibers with the components of the composite system, while the addition of Si3N4, on the contrary, causes the listed phenomena. The optimal sintering temperature of the materials of composite systems "cBN–NbN–microfibers" with the addition of oxide microfibers is 1900°C; for materials with the addition of non-oxide microfibers - 2000°C. For all composite systems, applying an external pressure of 7.7 GPa and increasing the temperature to 1600 ºС additionally increases the relative density. A slight increase in Young's modulus was found for the materials of the composite system "cBN–TaN–Al–Mg2B2O5w" at sintering temperatures of 1900-2000 oС. Poisson's ratio increases monotonically with the addition of microfibers to the material of the composite system "cBN–TaN–Al–Mg2B2O5w", increases slightly for the material of the composite system "cBN–TaN–Al–Al2O3w" at sintering temperatures above 1900 oC and for the materials of the composite system "cBN– TaN–Al–SiCw”, “cBN–TaN–Al–Si3N4w” at sintering temperatures up to 2000 oС. It was determined that the dynamics of the crack resistance of composite systems "cBN–TaN–microfibers" depends on the percentage of microfibers and the sintering temperature. For example, the addition of silicon carbide strengthens the composite material, raising the crack resistance to 7 MPa·m1/2. Mentioned opens up prospects for the use of such materials in tools for machining with impact (intermittent turning) at high temperatures within the cutting area. Product Description popup.authors Melniychuk Yuriy O. Nikitin Yuriy O. Osipov Oleksandr S. Petrusha Ihor A. Stratiychuk Denis A. popup.nrat_date 2024-01-12 Close