UDC 666.233
G. K. Burkat1, V. Yu. Dolmatov2, *, G. WITH. Aleksandrova1, E. D. Osmanova2, V. Myllymäki3, A. Vehanen3
1St. Petersburg State Technological Institute (Technical University), St. Petersburg, Russia
2 FSUE “SKTB “Technology”, St. Petersburg, Russia
3″Carbodeon Ltd. Oy”, Vaanta, Finland
*diamondcentre@mail.ru
The process of electrochemical deposition of zinc in the presence of boron-modified detonation nanodiamonds (pp. 3–9)
The influence of detonation nanodiamonds doped with boron during detonation synthesis (DNA–boron) on the process of electrochemical zinc deposition from a zincate electrolyte was studied. It is shown that the scattering ability (uniformity of the coating) increases by 2–4 times depending on the DNA–boron concentration, the electrical conductivity of the electrolyte does not change, and the corrosion resistance of the Zn–DNA–boron coating increases (according to corrosion currents) by 2.6 times in a 3% NaCl solution and by 3 times in the climatic chamber.
Key words: detonation nanodiamonds, boron, zinc, zincate electrolytes, corrosion endurance
UDC 661.811:546.62:537.534
AND. I. Pak*, K. N. Shatrova, N. THERE ARE. Aktaev
Tomsk Polytechnic University, Tomsk, Russian Federation
*ayapak@tpu.ru
Production of aluminum boride in the plasma of a high-current pulsed arc discharge (pages 10–15)
Experimental studies on the production of ultradispersed materials in a beam of electric discharge plasma containing aluminum and boron have been carried out. The beam is generated by a high-current impulse plasma accelerator and flows into an inert atmosphere (argon). According to qualitative X-ray phase analysis data, the obtained powder material consists of aluminum and aluminum boride α-AlB12.
Key words: electric discharge plasma, aluminum, aluminum boride, X-ray diffractometry, transmission electron microscopy.
UDC 621.315
V. I. Chasnyk1, I. P. Fesenko2, *, O. M. Kaydash2, V. I. Kushch2, G. P. Zakharchuk2
1State Enterprise Scientific Research Institute “Orion”, Kyiv, Ukraine
2V. M. Bakul Institute of Superhard Materials, NAS of Ukraine, Kyiv Kyiv, Ukraine
*igorfesenko@ukr.net
Theoretical and experimental evaluation of the dielectric permittivity of free-sintered AlN–Mo composites at frequencies of 3.2–10.0 GHz (pp. 16–31)
A theoretical evaluation of the dielectric permittivity of the insulator–spheroidal conductor grains system and its comparison with the experimentally determined value in the microwave region for free-sintered AlN–Mo composite materials with a molybdenum concentration of 16.6–24.0% (by volume) and a grain shape factor of 1.3–2.9 in the absence of macroscopic electrical conductivity are presented.
Keywords: aluminum nitride, molybdenum, shape factor, dielectric permittivity, microwave, percolation threshold, microwave radiation absorption.
UDC 537.528: 621.762.3
O. M. Syzonenko1, *, P. I. Loboda2, A. D. Zaichenko1, E. V. Solodkyi2, **, A. S. Torpakov1, M. S. Prystash1, V. O. Tregub1
1Institute of Pulse Processes and Technologies, National Academy of Sciences of Ukraine, Mykolaiv, Ukraine
2National Technical University of Ukraine “Kyiv Polytechnic Institute”, Kyiv, Ukraine
*sizonenko43@rambler.ru
**evgen.solodky@gmail.com
The effect of high-voltage electric discharge on the dispersion and structure of B4C powder (pp. 32–40)
The effect of high-voltage electric discharge on the dispersed system of distilled water–boron carbide powder was investigated, which allowed us to establish the regularities of the relationship between the discharge parameters and the dispersion and structure of the powder. It was shown that for effective dispersion of boron carbide powder, it is necessary to ensure the pressure amplitude of the compression wave of not less than ~ 100 MPa at a specific processing energy of ~ 20 MJ/kg.
Keywords: high-voltage electric discharge, dispersion, compression wave, boron carbide.
UDC 621.9.013/.015
T. Zhao1, 2, M. Agmell1, J. Persson1, V. Bushlya1, *, J. E. Ståhl1, J. M. Zhou1, *
1Division of Production and Materials Engineering, Lund University, Lund, Sweden
2Northwestern Polytechnical University, Xi’an, China
*jinming.zhou@iprod.lth.se
Correlation between edge radius of the cBN cutting tool and surface quality in hard turning (pages 41–51)
cBN cutting tools with superior mechanical properties are widely used in machining various hard materials. The microgeometry of cBN cutting tools, such as the edge radius, has great influence on the surface quality of components and tool life. For optimized tool geometry, it is crucial to understand the influence of the cBN cutting tool microgeometry on the machined surface quality. In this study, the attempt has been made to investigate the correlation between the cutting tool edge radius and surface quality in terms of the surface roughness and subsurface deformation through a FE simulation and experiment. Machining tests under different machining conditions were also conducted and the surface roughness and subsurface deformation were measured. Surface roughness and subsurface deformation were produced by the cutting tools with different edge radii under various cutting parameters. Both results from the FE simulation and machining tests confirmed that there was a significant influence on the surface quality in terms of both the surface roughness and subsurface quality from the edge radius. There is a critical edge radius of cBN tools in hard turning in terms of surface quality generated.
Keywords: cBN, cutting tool, hard turning, FE simulation, surface integrity.
UDC 621.9.013:621.914.2
A. Agic1, 2, *, M. Eynian2, S. Hägglund1, J.-E. Ståhl3, T. Beno2
1Seco Tools, Fagersta, Sweden
2Department of Engineering Science, University West, Trollhättan, Sweden
3Production and Materials Engineering, Lund University, Lund, Sweden
*adnan.agic@secotools.com
Influence of radial depth of cut on entry conditions and dynamics in face milling application (p. 52–66)
The choice of milling cutter geometry and appropriate cutting data for certain milling applications is of vital importance for successful machining results. Unfavorable selection of cutting conditions might give rise to high load impacts that cause severe cutting edge damage. Under some circumstances the radial depth of cut in combination with milling cutter geometry might give unfavorable entry conditions from the point of view of forces and vibration amplitudes. This phenomenon originates from the geometrical features that affect the rise time of the cutting edge engagement into the workpiece at different radial depths of cut. As the radial depth of cut is often an important parameter, particularly when machining difficult-to-cut materials, it is important to explore the driving mechanism behind vibration generation. In this study, acceleration of the workpiece is measured for different radial depths of cut and cutting edge geometries. The influence of the radial depth of cut on the dynamical behavior is evaluated in time and frequency domains. The results for different radial depths of cut and cutting geometries are quantified using the root mean square value of acceleration. The outcome of this research study can be used both for the better cutting data recommendations and improved tool design.
Keywords: milling, entry, radial depth, cutting edge, cutting force, vibration.
UDC 621.9.02.001.57
D. Johansson1, *, S. Hägglund2, V. Bushlya1, J.-E. Ståhl1
1Division of Production and Materials Engineering, Lund University, Lund, Sweden
2Seco Tools AB, Fagersta, Sweden
*daniel.johansson@iprod.lth.se
Sensitivity of Colding tool life equation on the dimensions of experimental dataset (p. 67–79)
In this work, 22 sets of cutting data and tool life for longitudinal turning of steel are analyzed using the Colding equation. When modeling tool life with a limited number of tool performance data points, the model error may be low for these points. Evaluating the model for test points not used when computing the model coefficients may give larger errors for these points. This work proves that the Colding model also provides sufficient precision when modeling data points not being used to create the model, and is therefore a well-functioning instrument for tool life modeling. The results also prove that for the selected data, the precision of the model can be greatly improved when the dimension of the data set is increased from 5 to 10 data points. Above 13 data points the precision improvements are negligible.
Keywords: machining, tool life, turning, the cooling equation.
UDC 621.923
Yu. D. Filatov1, *, V. I. Sydorko1, S. IN. Kovalev1, A. Yu. Filatov1, G. Montei2
1Institute of superhard materials named after IN. N. Bakulya National Academy of Sciences of Ukraine, Kyiv, Ukraine
2Higher National School of Mechanics and Microtechnics, Besançon, France
*filatov@ism.kiev.ua
Monitoring the accuracy of the shape of flat surfaces in the process of polishing parts of optics and microelectronics (pp. 80–87)
The possibility of in-process monitoring of the shape of the surfaces of optical parts directly during the polishing process using the technology of confocal chromatic visualization is shown. It was established that there is a linear relationship between the deviation of the signal shape from the rectangular shape and the change in the shape of the processed surface.
Key words: polishing, shape forming accuracy, shape deviation.
UDC 621.9.02
WITH. AND. Klymenko1, *, S. An. Klymenko1, A. WITH. Manokhin1, V. M. Beresnev2
1Institute of superhard materials named after IN. N. Bakulya National Academy of Sciences of Ukraine, Kyiv, Ukraine
2 Kharkiv National University named after IN.M. Karazyna, Kharkiv, Ukraine
*atmu@ism.kiev.ua
Features of the use of cutting tools made of polycrystalline cubic boron nitride with a protective coating (p. 88–100)
The results of studies of the performance of a cutting tool made of polycrystalline superhard material based on cubic boron nitride with a protective coating are presented. The hypothesis of increasing the durability of the cutting tool when turning hardened steel due to the decrease in temperature in the cutting zone is proposed, and the set of physical and mechanical properties of the protective coating required for this is analyzed.A protective coating based on boron nitride in an amorphous state was studied nii, which performs the role of a solid lubricant in the contact zone of the tool with the chip, reduces the temperature level in the contact zone due to the reduction of the contact length and cutting force, provides an increase in the durability and reliability of the tool, especially during the run-in stage.
Key words: cutting tool, polycrystalline cubic boron nitride, protective coating with amorphous-crystalline structure, cutting temperature, tool durability, turning, hardened steel.