Basis Of Carbide Research Articles

Исследование высокоскоростного взаимодействия образцов из карбидовольфрамового сплава с многокомпонентной связкой со стальной преградой

The samples on the basis of carbide and tungsten alloy were made by means of high-temperature sintering. The samples possess a perfect brand-new complex of physical, mechanical and functional properties. Penetrating ability of the samples concerning going through a steel obstacle with the interaction velocity of 1300 m/s is investigated. The comparison is made with the sample made of a basic alloy VNZH-90

The Tribological Properties of Superhard and Functional Coatings Based on Carbide and Boron Nitride

This study focuses on the tribological properties of superhard and functional coatings on the basis of carbide and boron nitride, which were optionally doped with powdered graphite and molybdenum disulfide. Coatings were obtained by highly concentrated short-pulse laser treatment of powder compositions on metal surfaces. The resulting coatings were subjected to wear tests under conditions of dry sliding friction with friction coefficient fixation, depending on the applied load and the composition of the powder composition. The results provide an idea of the degree of change in the coefficient of friction of coatings from the composition of powder compositions, as well as their alloying. The features of the behavior of boron carbide and nitride at high temperatures and their influence on the coefficient of friction are presented.

Phase equilibrium in system Ti-Si-C-B and synthesis of MAX phase layers in vacuum under the influence of electron beam

Composite layers on the basis of carbides and borides the titan and silicon on titanic alloy VТ-1 are generated at diffused saturation by electron beam treatment in vacuum. Formation in a composite of MAX phase Ti3SiC2 is shown. Thermodynamic research of phase equilibrium in systems Ti-Si-C and Ti-B-C in the conditions of high vacuum is executed. The thermodynamics, formation mechanisms of superfirm layers borides and carbides of the titan and silicon are investigated.

Thermodynamic modelling of phase equilibrium in system Ti-B-Si-C, synthesis and phases composition of borides and carbides layers on titanic alloyVT-1 at electron beam treatment in vacuum

Composite layers on the basis of carbides and borides the titan and silicon on titanic alloy VT-1 are generated at diffused saturation in vacuum. Formation in a composite of MAX phase Ti3SiC2 is shown. Thermodynamic research of phase equilibrium in systems Ti-Si-C and Ti-B-C in the conditions of high vacuum is executed. The thermodynamics, formation mechanisms of superfirm layers borides and carbides of the titan and silicon are investigated.

Prospects of application of nanostructured heterophase polyfunctional composite materials in aero-engine manufacturing

The article provides a brief overview of the features and applications of developed and investigated nanostructured superhard composite materials and coatings on their basis. The research carried out makes it possible to draw a conclusion of great prospects of using nanostructured composite materials on the basis of carbides, carbonitrides and diborides of transitional and refractory metals for aerospace objects. The use of new composite structural materials is the top priority in the area of improving technical and economic parameters of gas turbine engines. These materials are superior to traditional materials by their basic physical and mechanical properties several-fold. Numerous studies in this field indicate that the greatest progress in the development of new advanced structural composite materials can be expected on the way to creating materials based on polymeric, metallic, intermetallic, and ceramic matrices. At present, there is a distinct trend towards the creation of units and assemblies of multiple-start gas turbine engines and power plants with longer life and increased durability. Research in the area of using new-generation composite materials is carried out in almost all developed countries, primarily in the United States and Japan.

Prospects of application of nanostructured heterophase polyfunctional composite materials in aero-engine manufacturing

The article provides a brief overview of the features and applications of developed and investigated nanostructured superhard composite materials and coatings on their basis. The research carried out makes it possible to draw a conclusion of great prospects of using nanostructured composite materials on the basis of carbides, carbonitrides and diborides of transitional and refractory metals for aerospace objects. The use of new composite structural materials is the top priority in the area of improving technical and economic parameters of gas turbine engines. These materials are superior to traditional materials by their basic physical and mechanical properties several-fold. Numerous studies in this field indicate that the greatest progress in the development of new advanced structural composite materials can be expected on the way to creating materials based on polymeric, metallic, intermetallic, and ceramic matrices. At present, there is a distinct trend towards the creation of units and assemblies of multiple-start gas turbine engines and power plants with longer life and increased durability. Research in the area of using new-generation composite materials is carried out in almost all developed countries, primarily in the United States and Japan.

Технологии металлоплакирования в жилищно-коммунальном хозяйстве

The present article considers the issues of replacement of widespread compositions in equipment on the basis of carbide of tungsten, carbide of chrome, carbide of the titan, cobalt and nickel on much cheaper powders from cast iron and steel. The authors describe the experience in developing serial technological processes of worn-out detail restoration and hardening of newly-made details and units for the system of housing and communal services, consumer services, as well as automobile, textile, oil-extracting, food, paper-making and other industries

Kinetics studies of nano-structured cobalt–manganese oxide catalysts in Fischer–Tropsch synthesis

The nano-structured cobalt/manganese oxide catalyst was prepared by thermal decomposition of [Co(NH3)4CO3]MnO4 precursor, and was tested for the Fischer–Tropsch reaction (hydrocarbon forming) in a fixed-bed micro-reactor. Experimental conditions were varied as follow: reaction pressure 1–10bar, H2/CO feed ratio of 1–2 and space velocity of 3600h−1 at the temperature range of 463.15–523.15K. On the basis of carbide and/or enolic mechanisms and Langmuir–Hinshelwood–Hougen–Watson (LHHW) type rate equations, 30 kinetic expressions for CO consumption were tested and interaction between adsorption HCO and dissociated adsorption hydrogen as the controlling step gave the most plausible kinetic model. The kinetic parameters were estimated with non-linear regression method and the activation energy was 80.63kJ/mol for optimal kinetic model. Kinetic results indicated that in Fischer–Tropsch synthesis (FTS) rate expression, the rate constant (k) has been increased by decreasing the catalyst particle size. The catalyst characterization was carried out using different methods including powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) surface area measurements.

Characteristic properties of combustion and structure formation in the Ti-Ta-C system

Macrokinetic characteristics of the combustion of mixtures in the (100% − X)(Ti + 0.5C) + X(Ta + C) system with a variable mixing parameter X and initial temperature T0 of charge heating are considered. For compositions with X = 10 and 30%, an abrupt increase in the velocity Uc and temperature Tc of combustion as a result of passing two parallel chemical reactions of titanium and tantalum carbide formation is established. The Uc (T0) and Tc (T0) dependencies are linear for the mixture with X = 50%. By hardening the combustion wave, it is revealed that the primary structure formation in the combustion region starts from the selection of submicron grains of nonstoichiometric titanium carbide from the supersaturated titanium melt. In the investigated range of parameter X, synthetic products are single-phase and represent titanium-tantalum carbide. An increase in X results in a decrease in the size and microhardness of (Ti, Ta) C grains and a reduction of the relative density of compact synthetic products. The kinetics of high-temperature oxidation of alloys on the basis of carbide (Ti, Ta) C is studied. Ceramics produced at X = 10% are most heat-resistant.