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The development of new methods for obtaining materials with predetermined operational properties that ensure the durability and the wear resistance of friction units is an urgent problem in modern material science. The article considers the effect of ultrasonic pressing modes with simultaneously superimposed low-frequency amplitude modulation on the mechanical and tribotechnical properties of polytetrafluoroethylene. The comparison of the obtained research results of the new technology is carried out with the traditional pressing technology. The results of studies indicated that the technology of ultrasonic pressing with the simultaneous application of low-frequency amplitude modulation makes it possible to increase the mechanical properties of PTFE: the tensile strength by 15 %, elongation by 13 %, the elastic modulus by 8 %, the hardness by 12 %, while the intensity of the mass wear rate is reduced by 40 %, and the coefficient of friction by 27 %. [ABSTRACT FROM AUTHOR]

The article describes the influence of ultrasonic vibrations energy on the submolecular structure and tribotechnical properties of polymer composite materials based on polytetrafluoroethylene. Comparative analysis of the performed experiments showed that the introduction of ultrasonic vibration energy during pressing effects an increase in the wear resistance of polymer composite materials while maintaining low values of the coefficient of friction. In the friction process the submolecular structure changes because of a significant decrease in the size of crystallite blocks due to their fragmentation. [ABSTRACT FROM AUTHOR]

The method of making products from composite materials can be used in the production and manufacture of products from already known or new composite materials used in the oil and gas industry. The products manufacturing is carried out by pressing in a closed mold with application of ultrasonic influence and amplitude modulation. As a result of ultrasonic action and the imposition of low-frequency amplitude modulation on the pressed material, the tensile strength increased by an average of 5-6% and the elasticity module - by 12-14%. In this case, the relative elongation is reduced by 14-20%, and the wear rate is 12-14%. The new method allows significantly to increase the work resource and the slide bearings reliability used for making friction pairs of pumps and compressors of petrochemical industry. [ABSTRACT FROM AUTHOR]

The analysis of experimental data to study the change investigation of the carbide composite materials microhardness with the compositions (40TiC–10TiC (UDP)–50TiNi) % and (50TiC–49,5 TiNi–0.5 B) vol.%. was conducted in the article. It is established in the work that during the surface irradiation of polished samples with Ar+ + Zr+ ions with energy of 20 keV with a dose of ∼1017 ion / cm2, there is a significant change in the microhardness of the hard alloys described earlier compositions. Obviously, as a result the materials implantation produces quenched-in point defects caused by intensive heating and cooling of samples. The distribution of point defects is consistent with the surface change in the microhardness of the samples which were subjected to implantation. [ABSTRACT FROM AUTHOR]

In this paper, the causes of the drop in the mechanical properties in the process of manufacturing the “bend-out” part are investigated. On the basis of the obtained results, non-standard heat treatment is proposed, allowing to increase the mechanical characteristics to the initial values. Experimental data showing the validity of the proposed heat treatment regimes are given. [ABSTRACT FROM AUTHOR]

The article considers way to increase the microhardness of the surface of tungstenless hard alloy based on titanium carbide with a binding phase of intermetallic titanium nickelide (TiNi). The matrix in solid composite materials must exhibit the capability to arbitrary form making during the deformation process of the composite and to strengthen its positions and good wet particulate, providing a strong bond along the phase boundaries and high density during sintering. The increase of strength properties and hardness of composite materials are achieved by improving the microstructure, repairing defects in their structure, while improving the wetting processes with the binder phase. It was established experimentally that the process of irradiating the surface of polished samples the ions Ar+ and Zr+ with energy about 20 keV and a dose of 1017 ions/cm² of a solid alloy leads to a significant change in the microhardness of the material. It happens due to the formation of quenching point defects occuring during intense heating and cooling of composite samples. Structure formation occurs in extremely non-equilibrium conditions of interaction of the surface of tungstenless alloy with a concentrated energy flow, during the implantation the samples of solid alloys. The data are presented, visually showing that increasing the strength and microhardness is promising way to increase the wear resistance of products intended for earth works related to drilling wells and laying tunnels. [ABSTRACT FROM AUTHOR]

The paper is devoted to regularities of ultrasonic energy treatment effect on the structural features of a synthesized polymeric composite material based on the modified boron nitride polytetrafluoroethylene and its operational properties. The joint effect of ultrasonic treatment and filler particles is established to lead to the increase of crystallinity and block size in the structure of the crystalline phase. The studies in the elemental composition and chemical atomic state indicate the improvement of boron nitride-formed polytetrafluoroethylene structure, boron nitride inhibiting the formation of --C--Hx bonds and carbon defect states (C-C). This increases the molecular chains mobility of the polymeric matrix in a thin surface layer and defines more favorable redistribution of stresses in a friction contact and reduces the wear rate by 17 %, and the friction coefficient by 13.7 %. [ABSTRACT FROM AUTHOR]

Rational conditions for composite formation based on polytetrafluoroethylene with the increased wear resistance were defined. The influence of ultrasonic treatment parameters on mechanical and tribotechnical properties of polymeric composite material based on polytetrafluoroethylene was determined. A new PTFE-based composite material with high load capacity and wear resistance providing operation of friction units without lubrication was developed. The synthesis technology of polymer composite material based on PTFE modified with boron nitride was proposed for the production of sliding bearings. [ABSTRACT FROM AUTHOR]

Implementation of new designs of gear pumps with improved engineering specifications is important today. These specifications have both advantages and disadvantages: cyclic variation, relatively large volumetric loss, high operation noise. Gear pump performance and efficiency depend largely on the geometry of parts mating. So, a relevant task now is the definition of various defects in gears that lead to the interface clearance increase as well as internal loss increase of the working fluid, and decrease in performance. Gears of steel 20X2H4A was subjected to gas cementation first, and then to heat treatment. To assess the quality of heat treatment the spectral analysis was carried out, the chemical composition and impact toughness were determined, the microstructure was studied, and the measured hardness and microhardness of samples were changed. [ABSTRACT FROM AUTHOR]