UDC 620.22-621.921.34
B. T. Ratov1, V. A. Mechnyk2, *, M. O. Bondarenko2, V. V. Strelchuk3, T. O. Prikhna2, V. M. Kolodnitsky2, **, A. S. Nikolenko3, P. M. Lytvyn3, I. M. Danylenko3, V. E. Moshchil2, E. S. Gevorkyan4, V. A. Chyshkala5, A. S. Kosminov1, A. A. Shukmanova6
1NAO “Kazakh National Research Technical University named after K. I. Satpayev”, Almaty, Kazakhstan
2V. M. Bakul Institute of Superhard Materials, NAS of Ukraine, Kyiv, Ukraine
3V. E. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, Kyiv, Ukraine
4Ukrainian State University of Railway Transport, Kharkiv, Ukraine
5V. N. Karazin Kharkiv National University, Kharkiv, Ukraine
6Caspian University, Almaty, Kazakhstan
*vlad.me4nik@ukr.net
**vasylkolod56@gmail.com
Phase Formation and Physical and Mechanical Properties of WC‒Co‒CrB2 Composites Sintered by Vacuum Hot Pressing for Drilling Tools (pp. 3-16)
New data are presented on the influence of chromium diboride additives (in the range from 0 to 10% (by weight)) on the phase formation and physical and mechanical (fracture toughness, hardness, tensile strength during bending and compression) properties of composite materials based on hard alloy WC–6% (by weight) Co, formed by the method of cold pressing with subsequent vacuum hot pressing. It was found that the sintered composite samples consist of structural phases of the hexagonal WC group and the orthorhombic B2CoW2 group and inclusions of amorphous carbon. At the same time, the parameters of the B2CoW2 crystalline phase change depending on the CrB2 content. It was found that the addition of 4% (by weight) chromium diboride to the composition of the WC–6Co composite leads to a twofold increase in the fracture toughness KIc from 9.8 to 14.5 MPa∙m1/2 with a slight decrease in the hardness H from 15.1 to 13.9 GPa, as well as to an increase in the ultimate strength during bending Rbm from 2000 to 2500 MPa and the ultimate strength during compression Rcm from 5300 to 5500 MPa. It is shown that the indicated indicators are achieved due to the dispersion mechanism of strengthening and modification of the structure (stable reduction of the average grain size of the carbide phase, disappearance of pores at the site of the binding Co phase, formation of clusters of the inhibitor phase at the interphase boundaries) and the phase composition of the composites.
Keywords: composite, tungsten carbide, cobalt, chromium diboride, composition, concentration, vacuum hot pressing, structure, hardness, fracture toughness.
UDC: 669.017
V. Z. Kubliy*, S. V. Utkin, A. A. Bondar, S. Yu. Artyukh
Institute of Problems of Materials Science named after I. M. Frantsevich, NAS of Ukraine, Kyiv, Ukraine
*vasil.kubliy@gmail.com
Properties of phases in Mo–Fe–B alloys with boron content up to 40% (at.), annealed at subsolidus temperatures (pp. 17-26)
Concentration dependences of crystal lattice periods and microhardness HV for phases in Mo–Fe–B alloys with boron content up to 40% (at.), annealed at subsolidus temperatures were constructed. It was found that with increasing iron content in the (Mo), (αδ-Fe), s-MoFe and Mo2FeB2 phases, the periods decrease, and the microhardness increases for the (Mo) and Mo2FeB2 phases and decreases for (αδ-Fe), s-MoFe, m-Mo6Fe7 and R-Mo2Fe3. For most of the studied phases, the results obtained are in good agreement with the boundaries of the regions of phase homogeneity on the solidus surface constructed earlier.
Keywords: phase, alloy, system, phase composition, dependence, microhardness, period.
UDC 621.762.53
M. I. Upatov1,*, M. Yu. Efimenko1, D. Vleguels2, Yu. I. Bogomol1
1National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Kyiv, Ukraine
2Catholic University of Leuven, Belgium
*nikitaupatov@gmail.com
Directively crystallized three-phase eutectic composite of the B4C–TaB2–SiC system (pp. 27-35)
A three-phase eutectic composite B4C–8TaB2–40SiC (% (mol.)) was obtained by the method of directed crystallization. The properties of the obtained material were investigated: its structure is a fine-grained uniform three-phase eutectic of the B4C–TaB2–SiC system of lamellar type throughout the entire volume of the sample, the Vickers hardness value (33–34 GPa), crack resistance (3.9 MPa∙m1/2) were determined, the coefficient of thermal expansion of the composite in the temperature range 22–1600 °C was investigated.
Keywords: three-phase eutectic, coefficient of thermal expansion, boron carbide, silicon carbide, tantalum diboride.
UDC 621.623
Yu. D. Filatov1, *, V. I. Sidorko1, A. Yu. Boyaryntsev2, S. V. Kovalyov1, V. V. Garashchenko1, V. A. Kovalyov1
1V. M. Bakul Institute of Superhard Materials, NAS of Ukraine, Kyiv, Ukraine
2Institute of Scintillation Materials, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
*filatov@ism.kiev.ua
The influence of spectroscopic parameters of the processed material and polishing powder on the polishing performance of optical surfaces (pp. 36-46)
As a result of the study of the patterns of the influence of spectroscopic parameters of the processed material and polishing powder on the polishing performance and roughness of polished surfaces of parts made of optical glass, sieves, optical and semiconductor crystals, ceramics and polystyrene, it was established that that the intensity of removal of the processed material increases linearly with an increase in the number of molecular fragments in a particle of sludge removed from the processed surface, and decreases with an increase in the ratio of the frequencies of natural oscillations of molecular fragments in the particles of the polishing powder and the processed material. It is shown that with an increase in this ratio, the roughness parameters of the polished surfaces decrease linearly. It is established that the intensity of wear of the polishing powder decreases linearly with an increase in the ratio of the frequencies of oscillations of molecular fragments in the processed material and the particles of the polishing powder.
Keywords: polishing, spectroscopic parameters, polishing performance, surface roughness.
UDC 621.923
V. I. Lavrinenko1,, O. O. Pasichny1, V. G. Poltoratsky1, V. Yu. Solod2,, D. G. Muzychka2,
1V. M. Bakul Institute of Superhard Materials, NAS of Ukraine, Kyiv, Ukraine
2Dnipro State Technical University, Ministry of Education and Science of Ukraine, Kyiv, Ukraine
*lavrinenko@ism.kiev.ua
**v_solod@ukr.net
*** muzichka@ua.fm
Features of the shape change of the cutting surface of a grinding wheel in the circular direction during grinding with wheels with a mixture of NTM grinding powders and with a modified surface of their grains (pp. 47-59)
Features of the shape change of the cutting surface of a grinding wheel in the circular direction during grinding were studied and it was shown that it is uneven and has a wavy character. It is shown that the wave-like deformation of the surface is characteristic of both diamond and cubonite wheels, and is a natural phenomenon that reflects the process of removing the material being processed by the wheel. It is possible to get rid of the wave-like deformation by dressing the cutting surface. To obtain not a forced, but a natural deformation, it is necessary to use grains of compacts from cubic boron nitride micropowders, to involve mixtures of abrasive powders or to modify the surface of the grains of a superhard material. It is proved that if the surface of the grains is modified using chlorides, the cutting surface of the wheel has a broken wave profile in the circular direction and, as a result, the bearing capacity of the processed surface decreases.
Keywords: grinding wheel, cutting surface, wave deformation, surface roughness parameters, abrasive powders.
UDC 622.24.05: 621.921.34-419
O. P. Vinogradova, A. P. Zakora*, O. O. Shulzhenko, V. G. Gargin, O. M. Sokolov, D. V. Efrosinin, E. O. Zakora
V. M. Bakul Institute of Superhard Materials, NAS of Ukraine, Kyiv, Ukraine
*apz146@gmail.com
Comparative assessment of the performance of drill bits with a diamond-containing matrix and inserts made of diamond-containing composites (pp. 60-66)
A comparative assessment of the performance of drill bits with a diamond-containing combined matrix equipped with inserts made of a diamond-containing composite heat-resistant material AKTM and inserts made of a new composite wear-resistant material AKZM obtained by activated NRNT-sintering of diamond powders with the addition of n-layer graphene of the N002-PDR brand, which does not contain free silicon and has high strength and wear resistance. A complex of studies conducted after drilling a block of Korostyshivka granite of the X-category on a special stand, including the study of the working surface of the combined diamond-containing matrix of drill bits by the microscopic method and the contact method of measuring roughness, the study of the microprofile of the face surface formed during drilling, allowed us to conclude that the work efficiency of the bits equipped with AKZM inserts is higher than that of the bits equipped with AKTM inserts.
Keywords: drill bit, diamond powders, combined diamond-containing matrix, rock-breaking insert, workability, rock destruction efficiency, wear resistance, roughness of the microprofile of the working surface of the inserts and face.
UDC 666.762.5:621.914.1
Jinyang Xu*, Min Ji, Linfeng Li, Ming Chen
State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, P.R. China
*xujinyang@sjtu.edu.cn
Evaluation of polycrystalline diamond tools in milling pre-sintered and fully sintered zirconia ceramics (pp. 67-76)
Polycrystalline diamond (PCD) is a superhard tool material that can withstand harsh tool interaction when machining hard workpieces due to its excellent thermomechanical properties. Zirconia ceramics are one type of biomedical grade restorative materials that are widely used in clinical dental prosthetics due to their excellent biocompatibility and beautiful aesthetic effects. A series of experiments on milling zirconia using polycrystalline diamond tools were carried out. The main objective was to evaluate the wear resistance of such tools during milling zirconia. Two types of zirconia ceramic samples were investigated – pre-sintered and fully sintered 3Y-TZP ceramics. The tool performance was evaluated by wear, and the morphology of the worn tool surface was evaluated both by digital micro-cross-scope and surface topography measuring device. The main mechanisms regulating the wear of polycrystalline diamond tools in the case of processing various sintered ceramic samples have been identified.
Keywords: polycrystalline diamond tools, zirconium ceramics, milling of hardened parts, wear characteristics, wear mechanisms.
UDC 666.3:539.5
I. P. Fesenko1,*, L. O. Romanko1, V. I. Chasnyk2, L. M. Vovk3, Yu. M. Tuz4, A. V. Dovgal4, T. B. Serbeniuk1, O. M. Kaydash1, O. O. Bochechka1, V. P. Rukin2
1V. M. Bakul Institute of Superhard Materials, NAS of Ukraine, Kyiv, Ukraine
2Orion Research Institute, Kyiv, Ukraine Kyiv, Ukraine
3Ukrainian Research Institute of Special Equipment and Forensic Examinations of the Security Service of Ukraine, (ISTE SBU), Kyiv, Ukraine
4National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Kyiv, Ukraine
*igorfesenko@ukr.net
Electrophysical characteristics of a free-sintered ceramic composite AlN–TiN (pp. 77-79)
The electrophysical characteristics (electrical resistance, activation energy) of the aluminum nitride–titanium nitride ceramic composite in the temperature range of 27–215 °C were determined.
Keywords: free sintering, aluminum nitride, titanium nitride, temperature, electrical resistance, activation energy.