UDC 621.921.34
Jean Pierre Petitet (Villetaneuse, France)
Recent Trends in Superhard Materials Science and Technology
From both the research and the industrial development stand points, the superhard materials area is at the extreme limit of the using of traditional physicochemical and economical parameters. It is then not sure to clearly distinguish what will impulse the innovation between pure research and the industrial constraint. If the abrasive application remains the first application, the emergency of new applications of diamond and superhard materials with the combination of their specific properties in optics, thermics, chemistry, and electronics has been given rise to new scientific trends.
UDC 546.26-162
E. N. Yakovlev, V. P. Filonenko, N. F. Borovikov, T. D. Varfolomeeva, A. A. Antanovich (Troitsk, Russia)
Synthetic diamond polycrystals Ballas and Carbonado: thermodynamic conditions of formation and structure
The “supercooling” and thermodynamic driving force of the process of graphite-to-diamond transformation as a function of pressure during the formation of polycrystalline diamonds in the graphite + metal-catalyst system are calculated. The structures of Ballas and Carbonado diamonds synthesized at pressures of 6.0-8.0 GPa are compared.
UDC 666.233
N. V. Novikov, G. P. Bogatyreva, G. F. Nevstruev, G. D. Ilnitskaya (Kyiv)
Optimization of a Unified Technology System from Diamond Synthesis to Their Use
Production from diamond synthesis to diamond tool manufacturing consists of successive processes that form a Unified System (US) with a single goal, the optimization of which is ensured by a compromise of optimizations of individual subsystems. This is confirmed by examples of diamond extraction and powder manufacturing processes.
UDC 666.233.
G. P. Bogatyreva, M. A. Marinich, G. A. Bazaliy, N. A. Oleynik (Kyiv)
Resource-saving technologies for complex processing of diamond-containing raw materials
The results of theoretical and experimental studies on the complex processing of diamond synthesis products and the creation of resource-saving technologies are presented. The main aspects of the concept of processing diamond-containing raw materials are considered, which involves not only resource conservation and reduction of environmental damage due to the utilization of previously unused waste, but also the prevention of the influence of the environmental factor on the main technical and economic indicators of the enterprises.
UDC 546.26-162
V. Yu. Dolmatov (St. Petersburg), T. Fujimura (Tokyo, Japan)
Nanodiamonds
The structure of the peripheral structures of detonation diamond clusters is considered and it is shown that they play a decisive role in the processes of cluster aggregation and their interaction with matrix substances of composite materials. The elements of the mechanism of formation of ultradispersed diamonds are summarized, the process of their detonation synthesis is reconstructed based on the remaining “chemical labels” in the condensed detonation products.
UDC 621.928.4:621.921.1:621.922.34.
Yu. I. Nikitin, G. A. Petasyuk (Kyiv)
New methods of indirect diagnostics of characteristics of grinding powders from synthetic diamonds
The issues related to the development and practical implementation of indirect methods for diagnosing the characteristics of diamond powders are discussed. The methods for establishing the grain size and determining the grain composition of grinding powders of synthetic diamonds without using sieves and weighing fractions, determining their static and dynamic strength without conducting full-scale tests provided for by the current standard are presented. Using homogeneity as an example, attention is drawn to the need to expand the base of existing characteristics of grinding powders of synthetic diamonds for a more differentiated approach to assessing their quality.
UDC 669.018.25
A. F. Lisovsky (Kyiv)
Sintered hard alloys: self-organization of defects and the concept of structure formation
The processes of nucleation, growth and self-organization of defects in sintered hard alloys are considered. A correlation has been established between the structure, physical and mechanical properties and defect development. In hard alloys with high fracture toughness, deformation work and fatigue crack resistance, the rate of defect nucleation, growth and self-organization processes decreases by 10-30 times. This result has been achieved by increasing the energy absorption of the binder and carbide phases, reducing stresses in the binder phase and increasing the adhesion of contact and interphase surfaces.
UDC 621.9.025.7:62-987
V. I. Bugakov, Yu. S. Konyaev (Troitsk, Russia)
Highly efficient diamond tool manufactured using an original technology using high pressures and temperatures, new bonds and diamond materials
An original technology for manufacturing a diamond tool has been developed, including sintering its blank in a heat-insulating shell with electric heaters in a high-pressure chamber for 3-5 minutes. In this case, a new type of bonding and soldering compositions based on nickel with titanium and chromium diborides was used. A new type of bonding and soldering composition was developed and manufactured high-pressure cylinder-piston type with a working volume of up to 3 dm3, working pressure of up to 1.5 GPa and temperature of up to 1250 C. Replacement of large natural diamonds and diamond grinding powders with polycrystalline diamonds of the carbonado type and diamond compacts allowed to increase the technical and economic indicators of the tool by 1.5-2.0 times and expand the areas of its application. This technology is energy-saving, environmentally friendly and productive.
UDC 621.9: 658.5
T. G. Ivchenko (Donetsk)
Improving the reliability of carbide cutting tools in operation
Based on the theoretical studies, recommendations were developed to improve the reliability of carbide cutting tools by selecting operating conditions that ensure maximum efficiency of their use.
UDC 621.922.079:678
S. V. Sokhan (Kyiv)
Features of Finishing Diamond-Abrasive Machining of Spherical Ceramic Parts
Features of kinematics, loading conditions and tool wear during finishing abrasive machining of spherical parts using the free lapping method are studied. Analytical expressions are presented to describe the dependence of the free rotation speed of the tool, its wear on the kinematic-geometric and force parameters of the process. A fundamentally new method for controlling the free lapping process by changing the loading conditions of the tool is proposed, which ensures increased productivity and alignment of the stock removal along the part profile.
UDC 621. 793.7
V. E. Panarin, E. V. Dabizha (Kiev)
Development of technology for ion-plasma spraying of wear-resistant and corrosion-resistant coatings from eutectic iron-based alloys with interstitial phases
A laboratory technology for spraying eutectic coatings from iron-based alloys with interstitial phases by condensation stimulated by ion bombardment (SIB) has been developed. The technological process is based on industrial installations of the Bulat type. During the process of spraying the coatings, their crystallization mechanism changes, resulting in the formation of a structure of a “fine conglomerate of phases”. The phase composition of the sprayed cathode is almost completely preserved in the coating. The tribological properties of the obtained eutectic coatings are higher than those of the alloys in the cast state.
UDC 678.074.001.73:621.921.34
V. Yu. Dolmatov, A. P. Voznyakovsky, M. V. Veretennikova (St. Petersburg)
Modification of polymers with ultradispersed detonation synthesis diamonds (nanodiamonds)
Research was conducted on modification of polymers with ultradispersed detonation synthesis diamonds, in particular, with diamond charge. This led to improvement of the properties of all fluoroelastomers under study. On their basis, effective protective and antifriction films with elastic-strength characteristics increased by 1.5-3.0 times were developed.