UDC 539.2.669.0176:669.018
IN. M. Volkogon, G. WITH. Oleynyk*, Yu. AND. Fedoran, S. K. Avramchuk, A. IN. Kravchuk, A. IN. Kotko (Kyiv)
*oleynik@ipms.kiev.ua
The influence of the initial structural state of wurtzite boron nitride on the formation of the grain structure of ego-based materials.II.Structural transformations during the formation of the microstructure of material samples based on various types of BNv (pp. 1–13)
The results of the study of the microstructure of polycrystals obtained in the interval 1600–1800 °C at p = 8 GPa from powders of five varieties of wurtzite boron nitride are presented. Particles-plates of powders differed in size in the developed surface, thickness and substructure. It was found that the main factors determining the formation of the grain structure and phase composition of polycrystals are the thickness of the initial particles and their orientation, which is caused by the formation of a morphological texture during the compaction of the particle-plate system during sintering. These factors influence the following structural transformations in wurtzite boron nitride particles during sintering: dispersion of initial particles during mechanical chipping, their plastic fragmentation, and, as a result, the development of the process of sliding of disoriented fragments along the interfaces in the particles. In polycrystals based on powders with particles of the maximum thickness, the largest grain size is formed and the smallest degree of phase transformation of the wurtzite phase of boron nitride into sphalerite takes place; at the minimum particle thickness, these characteristics have the smallest and largest values, respectively.
Key words: boron nitride, wurtzite, sintering, structure, fragmentation, grain, particle.
UDC 666.295:620.17
T.AND.Prykhna*, A.IN.Starostyna (Kyiv, Ukraine)
D.Litzkendorf (Jena, Germany)
I.AND.Petrusha, S.AND.Ivakhnenko, A.I.Borymskyi, Yu.D.Filatov, M.G.Loshak, M.AND.Serga, V.N.Tkach, V.WITH.Turkevich, V.B.Sverdun, S.AND.Klymenko, D.IN.Turkevich, C. N.Dub, T.IN.Basiuk, M.IN.Karpets, V.THERE ARE.Moshchil, A.IN.Kozyrev, V.IN.Kovylyaev, G.D.Ilnytskaya (Kyiv, Ukraine)
T.Cabjos, P.Chartier (Poitiers, France)
- prikhna@mail.ru
Research of oxidation resistance, mechanical characteristics of materials based on MAX phases of Ti–Al–(C, N) systems and the possibility of their use as instrument bands and for polishing (p. 14–26)
The study of resistance to oxidation in air using the methods of thermogravimetry and differential thermal analysis showed that high-density samples of Ti3AlC2 are more stable than Ti2AlC and solid solutions of Ti2AlC1-xNx, and with an increase in nitrogen in the composition of solid solutions (up to x = 0.75), resistance to oxidation decreases. The material containing 89% (by mass) Ti3AlC2 (the rest Al2O3 and TiC), with a density of 99% of the theoretical one, had bending strength Rbm = 500 MPa, compression Rсm = 700 MPa, crack resistance KIc = 10.2 MPa×m0.5, hardness HRA = 70 GPa, HV = 4.6 GPa, Young’s modulus – 149.4±28.7 GPa. After the sintering of the MAX phase Ti3AlC2 with diamonds or c-BN (50% (by mass)) in thermobaric conditions at 5.5–7.7 GPa and 1350–1960°C for 0.07–1.0 h, it decomposes to form TiC and TiAl or TiB2, and a thin Al4C3 layer is formed at the interface with diamonds.Decomposition of Al4C3 in the composite material as a result of interaction with air moisture leads to the formation of cracks along the perimeter of diamonds, which causes complete destruction of the material within 1–2 weeks. The Ti3AlC2 powder proved to be effective for the final polishing of natural and synthetic jewelry crystals and competitive with ACM 2/1 diamonds in terms of productivity and processing quality.
Key words: MAX-phase, system Ti–Al–(C, N), diamond, cubic boron nitride, differential thermal analysis, thermogravimetry, high pressure, instrumental bond, polishing, mechanical characteristics.
UDC 661.657.636:544.3–971.2
IN. AND. Mukhanov, P. WITH. Sokolov, O. Brynza, D. Vrel, V. L. Solozhenko* (Paris)* vladimir.solozhenko@univ-paris13.fr
Self-propagating high-temperature synthesis of boron subphosphide B12P2 (p. 27–32)
Two new methods of obtaining nanopowders of boron subphosphide B12P2 by the method of self-propagating high-temperature synthesis are proposed. By sintering these powders at 5.2 GPa and 2500 K, dense polycrystalline B12P2 samples with microhardness HV = 35(3) GPa and stability in air up to 1300 K were obtained.
Key words: boron subphosphide, synthesis, high temperature, high pressure, hardness.
UDC 621.921.34-492.2:620.22-419
THERE ARE. M. Lutsak, O. AT. Bochecka*, V. M. Tkach, N. M. Bilyavina (Kyiv)
*edlutsak32@gmail.com
**bochechka@ism.kiev.ua
Study of the interaction in the Cu–Ti–diamond and Co–W–diamond systems during the wetting of diamond polycrystals and the impregnation of diamond nanopowder UDA under conditions of high pressure and temperature (pp. 33–39)
The regularities of the interaction of diamond–metallic alloy of the copper–titanium and cobalt–tungsten systems under conditions of thermodynamic stability of diamond are described. The possibility of metallization of diamond polycrystals is investigated of alloys and composites during their sintering in a high-pressure apparatus.
Keywords: diamond nanopowder, sintering, high pressure, impregnation coefficient.
UDC 621.793:539.61:669.018:620.1
V. M. Beresnev(Kharkov) S. A. Klymenko*(Kyiv)
I. N. Toryanyk(Kharkov)
A. D. Pogrebnyak(Sumy)
O. V. Sobol, P. V. Turbin, S. S. Grankin (Kharkov)
- beresnev-sept@yandex.ru
** klm@ism.kiev.ua
Superhard coatings of the systems (Zr–Ti–Si)N and (Ti–Hf–Si)N obtained by the vacuum-arc deposition method from the separated flow (pages 40–48)
Multicomponent solid coatings based on transition group metal nitrides doped with silicon were obtained by the method of vacuum-arc deposition with the use of pulse stimulation on the substrate and separation of the ion-plasma flow. The physico-mechanical and tribotechnical characteristics of the coating were studied. The possibility of their application as effective protective coatings for cutting tools is shown.
Keywords: protective coatings, vacuum-arc deposition method, metal nitrides, cutting tool.
UDC 621.623
IN. D. Kurilovich, Yu. D. Filatov*, V. A. Kovalev (Kyiv)
*filatov@ism.kiev.ua
Improving the efficiency of finishing natural stone products with a diamond-polymer fiber tool (pp. 49–58)
Methods for increasing the efficiency of processing natural stone with a diamond-polymer fiber tool in the preparatory operation before polishing are described. Parameters that affect the production of calibrated fiber are determined. Experimental samples of the tool are manufactured and tested. A tool design is proposed that ensures uniform wear of the working layer. The quality of the processed product surface is analyzed.
Keywords: fiber, conglomerates, calibration, cross-section, reflectometry, profilometry.
UDC 621.922.025
V. K. Starkov, S. A. Ryabtsev, E. G. Polkanov*, O. S. Kiskin (Moscow, Russia)
*v.starkov@stankin.ru
**tools@salut.ru
Comparative analysis of the performance of a tool made of cubic boron nitride and microcrystalline corundum during profile grinding of a shaped cutting tool (p. 59–67)
In production conditions, a comparative analysis of the performance of grinding wheels based on cubic boron nitride, microcrystalline corundum, and white electrocorundum was performed during profile grinding of a shaped long drawing from hardened high-speed steel. In the specific conditions of processing with shock loads and the need for frequent adjustment of the tool for accurate profiling, the circle on a ceramic bond made of cubic boron nitride showed significantly higher results in terms of process productivity, minimal time spent on cyclic adjustment and, in general, in reducing the labor intensity of forming the working profile of the broaching.
Key words: cubic boron nitride, microcrystalline corundum, white electrocorundum, tool performance, profile grinding, shaped broaching.
UDC 621.941:534.141
IN. M. Bushlya, O. AND. Gutnychenko*, J. M. Zhu, Ya.-E. Stoll (Lund, Sweden)
WITH. Gunnarsson (Hagfors, Sweden)
*volodymyr.bushlya@iprod.lth.se
**oleksandr.gutnichenko@iprod.lth.se
Wear and durability of cutters with KNB-based composites during continuous finishing turning of hardened cold-stamped steel (pp. 68–82)
The results of a comparison of the performance of tools equipped with composites based on KNB with and without a ceramic bond, as well as a composite containing wurtzite boron nitride, are presented. Workability was assessed by indicators of wear resistance, the amount of cutting force, quality parameters of the machined surface and the state of the surface layer of machined samples made of hardened cold-stamped steel during continuous turning. The studies were conducted under conditions of high-speed processing (vr = 120–180 m/min) both with and without SOTS. The best performance of the tool according to the specified criteria is ensured when using a composite on a ceramic bond containing a small amount of KNB.
Key words: KNB composites, wear, “white layer”, stamping steels, turning of hardened steels.
UDC 661.657.636:539.89
Y. Le Godec(Paris, France) M. Mezouar (Grenoble, France) O. O. Kurakevych, P. Munsch (Paris, France) U. Nwagwu, J. H. Edgar (Manhattan KS, USA) V. L. Solozhenko*(Villetaneuse, France)
- yann.legodec@impmc.upmc.fr
** vladimir.solozhenko@univ-paris13.fr
Equation of state of single-crystal cubic boron phosphide (p. 83–87)
The 300 K equation of state of cubic (zinc-blende) boron phosphide BP has been studied by in situ single-crystal X-ray diffraction with synchrotron radiation up to 55 GPa. The measurements have been performed under quasi-hydrostatic conditions using a Ne pressure medium in a diamond anvil cell. A fit of the experimental p-V data to the Vinet equation of state yields the bulk modulus B0 of 179(1) GPa with its pressure derivative of 3.3(1). These values are in good agreement with previous elastic measurements, as well as with semiempirical estimates.
Keywords: boron phosphide, high pressure, single crystal, equation of state.