UDC 548.33:539.26
F. Britun, A. V. Kurdyumov (Kyiv)
Martensitic Transformations in Carbon and Boron Nitride
The review considers the features and conditions for the implementation of martensitic transformations (MT) of graphite-like phases into diamond-like ones at high pressures. The greatest attention is paid to the discussion of thermally activated MT. It is shown that for ordered graphite-like structures, MT are the main type of direct phase transformations, and their crystallographic mechanisms determine the main features of the real structure of the resulting phases. The possibilities of using MT to obtain superhard phases and materials based on them are discussed.
UDC 535.343.546.171
I. P. Fesenko (Kyiv)
Dielectric ceramics with high thermal conductivity based on AlN
A series of studies of aluminum nitride was conducted to obtain a dense dielectric material with high thermal conductivity. The results of measuring the specific electrical resistance, as well as the permittivity and the tangent of the dielectric loss angle in the range of low and ultra-high frequencies are presented. The obtained material based on aluminum nitride has high thermal conductivity and low dielectric losses and can be used to manufacture elements of microwave devices.
UDC 621.921.34
G. P. Bogatyreva, G. F. Nevstruev, G. D. Il’nitskaya, V. A. Konovalov, V. N. Tkach (Kyiv)
Possibilities of Increasing the Strength of Diamond Retention in a Bond
The paper shows the possibilities of increasing the strength of diamond retention due to surface adhesion forces by means of a targeted increase in the degree of defectiveness of the surface of high-strength diamond grains when exposed to such distorting factors as mechanical or thermochemical treatment. Artificially created defectiveness of the surface of diamond powders made it possible to increase the degree of defectiveness with an insignificant (up to 10%) decrease in static strength, especially after thermochemical treatment, and contributed to an increase in diamond retention of high-strength diamonds in a metal bond.
UDC 621.922.02-49.2:697.8.052
Yu. D. Filatov, G. F. Gorbachev, V. I. Sidorko, V. G. Kramar, V. V. Skryabin (Kiev)
Regularities of the nonequilibrium polishing process of aluminosilicate materials
The article presents the results of a study of the regularities of the nonequilibrium polishing process of aluminosilicate materials based on the study of the hydromechanical interaction of the tool with the part and the cluster wear model. It is shown that by reducing the consumption of the process medium, the polishing productivity can be significantly increased.
UDC 541.183:669:65
V. M. Perevertaylo, O. B. Loginova (Kyiv)
Relationship between thermodynamic and interfacial activity of components during wetting of solids with melts
Data on surface tension of melts, wettability and contact interaction in diamond, boron nitride—metallic melt systems are analyzed and summarized. It is shown that there is a fairly general correlation between the adhesive and thermodynamic activities of the components of metallic melts. Taking into account the features of the energy of interatomic interaction in liquid metallic melts allows us to explain the appearance of minima on wetting isotherms and surface tension isotherms, and also largely determines the structure of the forming contact zone.
UDC 621.762.5
N. V. Novikov, A. A. Shulzhenko, N. P. Bezhenar, S. A. Bozhko, A. I. Borimsky, P. A. Nagorny (Kiev)
Kiborite: production, structure, properties, application
The relationship between the production conditions, structure and properties of a superhard polycrystalline material based on CBN — kiborite is shown. The prospects for its use as a tool and structural material are considered.
UDC 621.367. (035)
V. Yu. Dolmatov, G. K. Burkat, V. Yu. Saburbaev (St. Petersburg), A. E. Salko (Moscow), M. V. Veretennikova (St. Petersburg)
Production and properties of electrochemical composite coatings of noble and non-ferrous metals with ultradispersed detonation synthesis diamonds
A study was conducted on the effect of ultradispersed detonation synthesis diamonds (UDD) on a number of industrially important galvanic processes, such as galvanizing and gilding. The most commonly used electrolytes were used for the study. The UDD additive was studied in the range from 1 to 10 g/l. A method was developed for determining the UDD content in a zinc coating depending on the UDD content in the electrolyte.
UDC 621.928.4:621.921.1:621.922.34
N. V. Novikov, Yu. I. Nikitin, G. A. Petasyuk (Kyiv)
Express method of non-destructive testing of the dynamic strength of synthetic diamond grinding powders An express method of non-destructive testing of the dynamic strength of SA grinding powders is proposed based on information on the static strength indicators and the grain shape factor. The method is based on the developed empirical mathematical models and the corresponding computer software. In addition to the computer, a graphical version of the dynamic strength indicator is also provided strength of grinding powders using the given nomogram. The methodology of practical application of the proposed express method is presented, the results of testing for the reliability of the information obtained are given.
UDC 621.921.34.079-419
M. G. Loshak, L. I. Aleksandrova, A. L. Maistrenko, M. D. Levin, D. M. Miflig, S. A. Ivanov (Kyiv)
Quality control of diamond composites on a metal bond
The possibility of non-destructive quality control of diamond-containing composites on a metal bond by measuring the coercive force of the products was established. It is shown that between the coercive force of diamond segments of stone-cutting wheels on M6-14 and M6-14-1 bonds and their hardness (yield strength under compression) there is a linear relationship similar to the relationship between the coercive force of segments and wear resistance of diamond wheels when sawing granite. For this class of bonds and segment manufacturing technology, the level of coercive force of products characterized by high operational durability is determined.