Bulletin PNRPU. Mechanical engineering, materials science

Heat input to the electrode of the plasma torch and the product is determined by the near-electrode processes and heat transfer from the compressed arc. Processes occurring at the electrodes and electrode regions are complex and not sufficiently studied so far. In the present study attempted to estimate the magnitude of the voltage drop across the anode portion of the arc plasma torch at work on the current reverse polarity. Received a large amount of experimental data. This was carried out comparative studies of heat input to the anode of the plasma torch of different designs. The results of determining the voltage drop across the anode portion of arc plasma processing of metals. Asked to determine the rationale for the voltage drop across the anode portion of the arc using the measurement of heat input to the anode of the plasma torch. The magnitude of the voltage drop across the anode portion of the arc for the currents in the range of 50-300 A. The assumption that the anode material has virtually no effect on the anode voltage drop. The obtained values ​​of the anode voltage drop ( u a) suitable for determining the heat transfer during the estimations of work anode plasma torches and heating efficiency of the product.

One of the main problems of modern engineering is the problem of improving the reliability and durability of machines and mechanisms. The solution to this problem largely depends on improving the quality and performance characteristics of parts. In engineering technology has great potential for improving the performance properties of machine parts due to the microrelief on the working surfaces. Currently used methods of obtaining relief relief provide for the introduction of additional operations, the performance of which requires special equipment that increases the cost and increases the complexity of manufacturing. There is a need for research and development of such technologies for the manufacture of bearing parts, which involves the formation of a regular microrelief machined surfaces on traditional finishing operations of grinding and abrasive finishing. The properties of the abrasive wheel affect its performance. The grain size of the abrasive, the concentration of the grains and the diameter of the circle determine the number of grains, which are located on the elementary cutting contours, and it affects appropriately on the parameters and the stability of regular microrelief polished surface.

Developed advanced technology manufacturing parts oil pump module by isothermal forging burr. Pump module includes details of "The unit guide" and "Wheel of working". The most difficult part is to produce "Wheel of working" because it has a narrow blade with small radii of curvature. The conditions of work of oil pumps, the material selected for the details of the module that best meet the performance requirements. A review of possible technology manufacturing parts of the module. Selected technology based on isothermal forging. Technology tested mathematic modeling system QForm.

The article presents the analysis of the most important Russian and foreign publications on the process of sintering with the use of nanosized additives. It is shown that properties of sintered alloys are determined by the characteristics of raw materials and intermediate products carbide production that vary depending on various process parameters.It is established that the ultimate physical, mechanical and operational properties of carbide composites modified with nanoparticles are directly dependent on their microstructure, the ratio of volume fractions and particle sizes. Reduction of particle size to nanoscale condition significantly affects the diffusion processes. Using nanoparticles additives can significantly reduce the sintering temperature.

Based on the analysis of contemporary problems for creation of the titanium-carbon materials for medical implants shows the relevance of research on the formation of surfaces with high specific surface and carbon nanostructures, causing locally-selective adhesion and growth of cells. Presents the results of experimental studies the effect of surface treatment of titanium alloy VT1-0 in the subsequent deposition of carbon structures, including multiwalled carbon nanotubes. Have been proposed two techniques of titanium surfaces treatment - sandblasting and microarc oxidation. A comparative analysis of the condition of the surface after each type of processing performed using scanning electron microscopy and local microprobe analysis showed that abrasive blasting and microarc oxidation increases the surface area on the background of different susceptibility to subsequent synthesis of carbon nanoclusters. The structure of the sample surface after sandblasting presents major depression by up to 25 μm with difficult to remove abrasive particles that prevents uniform distribution of the pre-catalyst for growth of carbon nanotubes. During the microarc oxidation is formed more favorable regular pore structure of the oxidized layer with a pore size of 0.2-2.0 μm, which is uniformly and tightly can be precipitated nanotubes. Formed amorphous layer of titanium dioxide with a thickness 9-15 µm contains phosphorus and calcium in the form of calcium titanate and titanium diphosphate. The pores formed in the oxide layer also contain carbon nanostructures, most will promote osseointegration of the implant. The results are a step in the implementation of the project on creation of implants with carbon nanoclusters to improve fixing and proliferation of osteoblasts.

Technical and technological problems are in-process certain engineers arising up at creation of stamps of non-standard form are caused by absence of the specialized rigging for machine-tools numerically controlled. Possibility of application unequal the rigid of connections with a tightness is considered at creation and modernization of the heads of machines existing the dividing with numerical program control. With application of original mathematical model the multi contact problem of weed the eccentric connection with a tightness with three details (three steel clowns) in contact on radial and axial landings was solved. The received earlier graphic dependence of size of load ability the unequal the rigid of connections with a tightness from temperature of environment and as a result of temperature of components of the connection applied in the dividing heads of machines with numerical programming control is experimentally confirmed. Practical recommendations to destination of tight nesses in landings of a dividing head, choice of sizes of eccentricity of components and optimum temperatures for a press back allowing to provide are made: decrease in concentration of tension in dangerous sites of details, providing operating conditions of a design in an elasticity zone. The presented recommendations are intended for designers and technologists for the purpose of realization of qualitative designs and effective technologies of assembly new and operation of the heads existing the dividing on a basis on application the unequal the rigid of connections with a tightness as tool equipment of machines with numerical programming control.