UDC 539.89: 620.178
THERE ARE. M. Suprun1, *, V. AND. Kalenchuk1, S. AND. Ivakhnenko1,
AND. M. Kutsai1, V.In Lysakovsky1, O.AND.Zanevsky1,
Wang Dufu2, Wang Shenlin2
1Institute of superhard materials named after IN. N. Bakula
National Academy of Sciences of Ukraine,Kyiv, Ukraine
2Company “Best Environment Ltd”, Jinan, China
*alona_suprun@mail.ru
Defect-impurity composition of single crystals of diamond type Ib of cubic habit (p. 3–8)
Under conditions of high pressure and temperature, single crystals of type Ib diamonds with a size of up to 5–6 mm and a weight of up to 2.4 carats were grown. With the help of infrared and optical microscopy, as well as the method of selective etching, the defect-impurity composition and dislocation structure of such crystals were investigated. Minimization of the growth temperature made it possible to obtain crystals of type Ib of cubic habit, in which there are defect regions in the form of a cone with a base diameter of 0.2–1.8 mm and a height of 0.5–2.5 mm. The study of cone-shaped defect areas using selective etching showed that etching pits when they reach the surface of the faces have a tetragonal shape, the density of dislocations in them exceeds the density of dislocations in crystals grown under normal conditions by 70–100 times. The observed defect regions are formed during the growth of diamond crystals when the temperature drops by ~30–35°С at the crystallization front due to the increase in heat dissipation in the direction of the seed crystal.
Key words: diamond, single crystal, habitus, defect-impurity composition, IR spectroscopy, selective etching method.
UDC 620.22:669.018.25
AND. F. Lysovsky*, N. AND. Bondarenko, S. AND. Davydenko
Institute of Superhard Materials named after IN. N. Bakula
National Academy of Sciences of Ukraine, Kyiv, Ukraine
*lisovsky@ism.kiev.ua
Structure and properties of the diamond–WC–6Co composite doped with 1.5% (by mass) CrSi2 (pages 9–21)
The effect of chromium and silicon on the structure of the diamond–WC–Co composite doped with chromium disilicide was studied at the meso-, micro-, and submicron levels. It was established that under the conditions of the formation of the diamond–WC–Co + CrSi2 composite structure, chromium and silicon do not dissolve in the diamond and WC carbide particles, forming a solid solution of Co(W,C,Cr,Si), thereby reducing the energy of the packing defect, which contributes to the polymorphic transformation of Co(FCC)®Co(HPU). Chromium interacts with carbon atoms in diamond and WC carbide, resulting in the disappearance of the graphite layer in the diamond/Co phase contact zone, and the formation of Co3W3C carbide in the WC–Co matrix. Chromium and silicon provide good retention of diamond particles in the WC–Co matrix, increase the compressive strength value of the diamond–WC–Co + CrSi2 composite.
Keywords: structure, packing defect energy, composite, diamond.
UDC 669.295.539.121.537.534
AND. D. Pogrebnyak1,*, S. AT. Borba1, Ya. AT. Kravchenko1,
THERE ARE. AT. Tleukenov2, S. IN. Plotnikov2, V. M. Beresnev3,
Y. Takeda4, K. Oyoshi4, A. I. Kupchyshyn5
1 Sumy State University, Sumy, Ukraine
2 East Kazakhstan State Technical University
university named after D. Serikbaeva, g.Ust-Kamenogorsk, Kazakhstan
3 Kharkiv National University named after IN. N. Karazin,
Mr. Kharkiv, Ukraine
4 National Institute of Materials Science, Tsukuba, Japan
5 Kazakhstan National Pedagogical University
named after Abaya, g. Almaty, Kazakhstan
*alexp@i.ua
The effect of implantation of a nanostructured coating (TiHfZrVNbTa)N with a high dose of N+ ions (1018 cm–2) on its microstructure, elemental and phase composition, and physical and mechanical properties (pp. 22–32)
The structure and properties of nanostructured multicomponent coated (TiHfZrNbVTa)N implanted with a very high (1018 cm–2) dose of N+ ions were studied. As a result of the implantation of ions in the surface layer of the nanostructured coating, a multilayer structure consisting of amorphous, nanocrystalline (dispersed) and nanostructured (with initial dimensions) nanolayers is formed. In the depth of the coating, two phases are formed – fcc and gpu with a small volume content. The concentration of nitrogen near the surface reaches 90% (at.) and then decreases with depth. In the initial state after deposition, the nanohardness of the coating, depending on the deposition conditions, ranges from 27 to 34 GPa. As a result of implantation, the hardness decreases approximately to the depth of the projective run of ions – up to 12 GPa, and then increases with depth to 23 GPa. Research was conducted using Rutherford backscattering, raster electron microscopy with microanalysis, high-resolution electron microscopy (with local microanalysis), X-ray diffraction, nanoidentification, and wear tests.
Key words: implantation, nanostructured multicomponent coating, microstructure, elemental and phase composition, physical and mechanical properties.
UDC 666.762.93:536.2:546.281.26
IN. G. Kulych*, A. L. Maistrenko, V. N. Tkach, Ya. AND. Semblance
Institute of Superhard Materials named after IN. N. Bakula
National Academy of Sciences of Ukraine, Kyiv, Ukraine
*v.kulich@ukr.net
Saturation of capillary pores of silicon carbide briquettes with liquid-phase carbon-containing solutions before reaction sintering (pp. 33–45)
The process of increase has been studied carbon saturation of a porous silicon carbide briquette by means of repeated infiltration of petroleum coke solutions instead of the traditionally used solid-phase lamp soot powder or finely dispersed graphite powder intended to ensure reactive sintering of silicon carbide with the aim of reducing the proportion of free silicon remaining in the structure after sintering.
Keywords: reaction-sintered silicon carbide, carbon, petroleum coke, silicon, impregnation, coking, secondary silicon carbide.
UDC 621.921.34:546.27:536.4/.631:538.945
S. Tarelkin1, 2, 3, *, V. Bormashov1, 2, M. Kuznetsov1, S. Buga1, 2, S. Terentiev1, D. Prikhodko1, 2, Golovanov1, 2, V. Blank1
1Technological Institute for Superhard and Novel Carbon
Materials, Moscow, Troitsk, Russia
2Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, Russia
3National University of Science and Technology MISiS, Moscow, Russia
*sergey.tarelkin@gmail.com
Heat capacity of bulk boron doped single crystal HPHT diamonds in the temperature range from 2 to 400 K (p. 46–51)
Heat capacity Ср of boron-doped single crystal diamonds grown by the temperature gradient method were studied. Boron content was about < 1016, ~ 1018 and ~ 1020 cm–3. Heat capacity data for all tested crystals match well within the measurement accuracy (1%) in the temperature range of 150–400 K and obey the Debye law. At low temperatures, the heat capacity follows a linear law, possibly due to metallic inclusions in the diamond bulk. Using this data, the amount of metal can be calculated for each sample.
Keywords: synthetic diamond, boron-doped diamond, superconductivity, heat capacity, cryogenic temperatures.
UDC 621.923: 621.922
IN. AND. Lavrinenko1, *, V. Yu. Malt2, **
1Institute of superhard materials named after IN. M. Bakulya National Academy of Sciences of Ukraine, m. Kyiv, Ukraine
2Dniprodzerzhyn State Technical University, Kamianske, Ukraine
*lavrinenko@ism.kiev.ua
**v_solod@ukr.net
Oxidation or oxide materials in the treatment zone with NTM wheels as a factor influencing the grinding process indicators (pp. 52–60)
The application of indirect measures to stimulate oxidation processes for grinding processes, as well as the use of oxides and materials prone to oxidation in the working layer of wheels, is considered, since the direct introduction of oxygen into the treatment zone, which is an important factor in changing the tribotechnical characteristics of contact surfaces, causes certain difficulties.
Keywords: oxidation, treatment zone, grinding, wheels made of superhard materials, oxides, plasma effect, films.
UDC 666.792.34:539.89
V. Z. Turkevich*, D. A. Stratychuk, D. V. Turkevich
Institute of Superhard Materials named after IN. N. Bakulya National Academy of Sciences of Ukraine, Kyiv, Ukraine
*vturk@ism.kiev.ua
Thermodynamic calculation of the state diagram of the Al–V–C system at a pressure of 7.7 GPa (pages 61–65)
With the help of models of phenomenological thermodynamics with interaction parameters obtained on the basis of experimental data on phase equilibria at high pressures and temperatures, the state diagram of the Al–B–C system at a pressure of 7.7 GPa was calculated.
Key words: state diagram, high pressure, high hardness composites
UDC 004.65:621.921.34
IN. N. Kulakovsky, V. N. Kolodnytskyi*, V. IN. Tsegelniuk, I. IN. Skvortsov
Institute of Superhard Materials named after IN. N. Bakulya National Academy of Sciences of Ukraine, Kyiv, Ukraine
*stmj@ism.kiev.ua
About one approach to building an information system for managing scientific knowledge in the subject area “Superhard Materials” (pp. 66–69)
An approach based on the heuristic method of pattern recognition to the construction of an information system for managing scientific knowledge presented in the form of electronic documents of various types is considered. The algorithm of automatic classification of documents by scientific directions in the subject area “Superhard materials” is described.
Keywords: superhard materials, information system, automatic classification, electronic documents.