UDC 669.018.25
L. I. Aleksandrova, V. P. Bondarenko, T. V. Nayuk, N. A. Yurchuk (Kyiv)
The effect of thermal cycling treatment of tungsten carbide hard alloys on their structure and properties. Part 1
The possibility of increasing the plastic characteristics (while maintaining strength) of finally sintered high-cobalt hard alloys of grades VK15 and VK20 using thermal cycling treatment is shown. It is established that an increase in the level of plastic characteristics of these alloys is ensured by changing their structural state.
UDC 526.2:666.233
V. V. Korolkov, B. N. Tarasevich, I. I. Kulakova, G. V. Lisichkin (Moscow)
Interaction of a chlorinated synthetic diamond surface with C-nucleophiles
Several reactions of C-nucleophiles with the chlorinated surface of two types of diamond were implemented. UDA-SF detonation nanodiamond and DALAN synthetic diamond have been employed in the above procedures. The grafting of butyl and nitrile groups has been achieved. However the grafting of phenyl groups via reaction with PhLi is still a problem. For the first time the NMR-H1 spectroscopy of suspension was used for elucidating the structure of a grafting compound.
UDC 666.233.–621.385
V. Yu. Dolmatov (St. Petersburg, Russia)
Modern industrial technology for producing detonation nanodiamonds and their main areas of application. Message 1
The most rational parameters of modern detonation synthesis of nanodiamonds and their chemical purification are briefly described, the main properties of nanodiamonds are presented.
UDC 544.72
L. Yu. Ostrovskaya (Kyiv) Peculiarities of wettability of nanocluster coatings
Models of wetting of structures with different surface topography (smooth, rough, formed from an ensemble of clusters) are considered. Using the presented models, the wettability features of nanocluster coatings based on carbon and titanium dioxide are explained depending on their thickness, roughness, heterophase, fractality. The possibilities of controlling the wettability of nanocluster films by changing the surface morphology either by using clusters of different sizes (from nano- to micron) during film deposition or by modifying the surface by annealing are considered.
UDC 621.762.242: 669.27
V. P. Bondarenko, I. V. Andreev (Kiev)
Kinetic Analysis of WO3 Reduction Reactions with Hydrogen in a Closed Reactor
A kinetic analysis of the process of tungsten reduction with hydrogen in a closed reactor is described. It is shown that when using a closed reactor, a simultaneous decrease in both the reaction rate constant and the activation energy of the reduction process is observed, which is explained by the replacement of a heterogeneous process with a homogeneous one. The effect of external and internal diffusion inhibition on the reduction process in a closed reactor is estimated.
UDC 546.26:545.345.67:539.216
S. P. Starik, O. G. Gontar, B. A. Gorshtein, V. Yu. Gorokhov, S. M. Dub, O. M. Kutsay (m. Kiev)
Multi-spherical anti-reflective interference coatings with dry diamond-like melt for the range of 8-12 microns
The optical and mechanical properties of carbon α-C:H coatings and their occurrence depending on the technological parameters of precipitation were investigated. The spherical coating was designed and created with superior mechanical and optical performance characteristics. The complex nanohardness increased from 0.5 GPa for classic translucent coating to 5 GPa when diamond-like α-C:H melt was introduced into the warehouse. For wear resistance, the coating should be brought up to group “0” according to OST 3-1901-85 and will ensure the integral transmittance of the ICH vibration in the range of 8-12 microns at around 98 ‰.
UDC 681.7.023.4
V. V. Rogov (Kyiv) A. Ya. Danko (Kharkov) V. G. Senchishin, A. Yu. Boyarintsev (Kyiv)
Sapphire and ruby (α-Al2O3) cutters for blade finishing of scintillation materials
A technology for finishing sapphire parts has been developed, which, in combination with a certain crystallographic orientation of the cutter’s cutting element, its sharpening geometry, body design and turning modes, ensured the achievement of a condition of the treated surfaces that meets the requirements imposed on optical parts and is not inferior to the level obtained when turning with cutters from scarce crystals of natural diamond.
UDC 621.923:[621.922:621.921.34]
V. I. Sidorko (Kyiv)
Theoretical analysis of wear of the working layer of the tool for finishing of parts made of natural and synthetic stone
The results of the theoretical analysis of the interaction of the surfaces of the tool and the workpiece in the contact zone are presented. A method for calculating the productivity of the removal of the workpiece during finishing of natural and synthetic stone is described. An equation for the coefficient of filling the surface of the tool with the working layer is obtained, allowing to optimize its design.
UDC 519.711.3:621.762.5
V. A. Dutka, V. P. Pereyaslov, S. A. Ivanov, L. M. Bologova (Kiev)
Numerical analysis of the impact of the design of the technological unit and heating mode on the temperature of the working layer when baking it on the drill bit body
The results of numerical modeling of the temperature field in the volume of the working layer of the drill bit during its baking on the drill bit body under a pressure of 100-200 MPa are presented. The heating process was carried out by direct passage of an electric current of industrial frequency through the bit body, the working layer and the elements of the technological unit. Heating modes were considered at which the sintering temperature level of the working layer of the bit was reached within 10-20 min using one of four configurations of the MG-1 and SG-T graphite heater. It is shown that when choosing a heater material with the appropriate specific electrical resistance, its design and heating mode, it is possible to bake the working layer on the drill bit body, preventing deformation of the punches of the technological unit.
UDC 669.262.621.
M. A. Hryhoryan (Yerevan) T. G. African (Ghavar)
Conditions for ensuring the angle of inclination of the grains in the working layer of the extruded circle
The dependence of the grain wear of abrasive tools on the location of the grain axis relative to the direction of the force affecting it has been established. An effective method of orientation of the grains of abrasive tools by extrusion is proposed.