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Information × Registration Number 0225U001485, (0122U000399) , R & D reports Title Formation of structure of polycrystals and composites by sintering at high diamond pressures powders synthesized in magnesium-based systems popup.stage_title Формування структури полікристалів та композитів спіканням за високих тисків алмазних порошків, синтезованих в системах на основі магнію Head Bochechka Oleksandr O., Доктор технічних наук Registration Date 01-02-2025 Organization V. Bakul Institute of superhard material of the National Academy of Sciences of Ukraine popup.description1 Establishing patterns of structure of heat-stable and wear-resistant diamond polycrystals and composites under the action of high pressure and high temperature on diamond powders synthesized in magnesium-based systems, using additives that form stable compounds with carbon, for use as working elements of drilling and cutting tools. popup.description2 The process of diamond crystallization in Mg–Zn– C and Mg–Zn– B–C systems was carried out under 8 GPa at 1800 °C. The hardness of a polycrystalline element sintered from the 40.4 μm powder is 87% of the hardness of a single crystal natural diamond, and its wear resistance during stone turning is 11 times higher than the wear resistance of a sample sintered from powder synthesized in Ni–Mn–C system. It is shown that in the C–Ti–O system, during sintering of diamond powder, oxygen present in the pores between diamond particles reacts with Ti, and this makes the interaction of diamond with Ti impossible. The access of oxygen to the contact surfaces between diamond and Ti can be blocked by coating diamond grains with titanium. Such a coating intensifies the compaction process in the initial period, also reduces the sintering temperature at which the maximum compaction is achieved, from 1800 to 1450 ° C. The density of samples obtained from titanium-coated diamonds is 3.44–3.46 g/cm3, hardness 60–65 GPa. The wear resistance of the blade tools made of sintered diamond powder grown in the Mg–Zn–C growth system without Ti coating and from powder with Ti coating on the diamond grains grown in Mg–Zn–B–C system was investigated. During turning of the aluminum alloy АК12М2МгН, both in the case of the presence of Ti coating on the diamond grains and in the absence of coating, the tool does not wear out. After turning the Al2O3 ceramic sample, a wear chamfer is observed on the back surface of the tools. The change in dielectric properties of polycrystalline samples sintered from synthetic diamond powder at a pressure of 8 GPa and different temperatures was investigated. Adding B to the Mg–Zn–C growth system increases the conductivity of the synthesized powder by 4 orders of magnitude, and applying Ti to the diamond powder increases the conductivity of the system of bonded diamond particles by another 1 order of magnitude: the resistivity of the studied samples is 1–2.32 Ohm cm. Product Description popup.authors Yefremov Oleksii O. Isonkin Oleksandr M. Itsenko Pavlo P. Bilorusets Viktor V. Bilochenko Vasil P. Beliaieva Tetiana M. Vienikov Vladyslav O. Havrylova Valentyna S. Hontar Oleksandr H. Horokhov Viacheslav Yu. Zharovskyi Hryhorii Ya. Kamenskykh Dmytro S. Kuzmenko Yevhen F. Kuryliak Tetiana O. Kushch Olha V. Leshchenko Olha V. Lypova Valentyna D. Lysovenko Serhii O. Lohinova Olha B. Liamtseva Anna O. Melniichuk Yurii O. Osipov Oleksandr S. Perevertaylo Vasyl M. Petasiuk Hryhorii A. Pyrohov Volodymyr A. Podoba Oleksandr P. Poltoratskyi Volodymyr H. Romanko Liudmyla O. Silchenko Yaroslav L. Sadokhin Viktor P. Sadokhin Vitalii V. Syrota Yurii V. Sokolyuk Dmytro V. Staryk Oksana M. Staryk Serhii P. Tkach Vasyl M. Turkevych Dmytro V. Fefilatiev Mykola V. Fylypovych Andrii H. Cherniienko Oleksandr I. Chumak Anatolii O. Shmehera Roman S. Shmehera Serhii V. Yankovska Alevtyna M. popup.nrat_date 2025-02-01 Close