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The article presents the results of a study of the influence of temperature on the coefficient of friction of radiation-modified fluoroplastic when lubricated with hydraulic fluid. A friction pair of radiation-hardened fluoroplastic with 40X steel, when lubricated with AMg-10 hydraulic fluid, has good anti-friction properties. The friction coefficient F4M when lubricated with hydraulic fluid is low. At a temperature of 90 °C and a speed of 2.5 m/s, the friction coefficient F4M at a load of 2.003 MPa is 0.04. Bushings made of F4M paired with steel 40X can be used in pumps when lubricated with AMg-10 working fluid. [ABSTRACT FROM AUTHOR]

The article presents the results of tribological tests of a thrust bearing made of materials BrOF 6.5-0.15 and "Hardkarb-TP" when lubricated with a lead-bismuth metal melt under heating conditions up to 600 °C. The effect of BrOF 6.5-0.15 and "Hardkarb-TP" on the friction coefficient was studied in the ranges of load 0.17–1.0 MPa, velocity 0.05–0.23 m/s, and temperature 250–600°C. It has been established that the friction pair "Hardkarb-TP"-40X13 has the best antifriction properties. At a temperature of 500 °C and a speed of 0.1 m/s in the load range of 0.17–1.0 MPa, the "Hardcarb-TP" friction pair – 40X13 has a friction coefficient of 0.18–0.22, which is up to 2 times less than the friction coefficient of the BrOF pair 6.5-0.15 – 40X13. [ABSTRACT FROM AUTHOR]

The article presents the results of tribological tests of a thrust bearing made of materials BrOF 6.5-0.15 and "Hardkarb-TP" when lubricated with a lead-bismuth alloy melt under heating conditions up to 600 °C at a load of 0.17 - 1.0 MPa and sliding speeds of 0.05-0.23 m/s. At a temperature of 400°C, the friction coefficient of the BrOF 6.5-0.15– 40X13 pair is 1.85 times greater than the friction coefficient of the Hardkarb-TP–40X13 pair. With an increase in temperature above 500°C, the friction pair BrOF 6.5-0.15 - 40X13 is not operational. At a temperature of 500 °C, a speed of 0.16 m/s and a load of 1.0 MPa, the Hardkarb-TP friction pair - 40X13 is operational, has a friction coefficient of 0.19. The best antifriction properties have a pair of friction "Hardkarb-TP" - 40X13. [ABSTRACT FROM AUTHOR]

The results of high-temperature tribological tests of carbon-containing materials during friction against heat-resistant stainless steel X40Cr13 in the temperature range from +300 to +800 ° C in atmospheric conditions are presented. The modified friction surface of the material "Argolon-2D" in the environment of CuO-PTFE and CuSe-PTFE improves antifriction properties, reduces the value of the friction coefficient. The range of the friction coefficient values of the modified surface Argolon-2D+CuSe-PTFE at a temperature of +400°C is 0.16–0.19, and at a temperature of +500°C - 0.21–0.26. At a speed of 0.05 m/s, the friction coefficient of the modified surface Argolon-2D+CuSe-PTFE is 27% less than on non-processed surface, and the friction coefficient of the modified surface Argolon-2D+CuO-PTFE is 46% less than on non-processed surface. [ABSTRACT FROM AUTHOR]

A methodology has been developed for repairing shrouds of turbine blades made of titanium alloy VT41 by creating a wear-resistant coating using a 2-stage technology for obtaining a wear-resistant coating. Based on the results of a numerical calculation of heating with subsequent melting of the coating under the Stefan boundary conditions, the level of the heat flux power density and the time of its action during laser melting of the coating was determined. The distribution of temperature in the coating up to the moment of its fusing to the base is determined. The values of the heat flux for the preservation of the strengthening phase of aluminum oxide in the coating are determined. The prospects of the process of laser cladding of coatings containing particles of aluminum oxide for wear protection of friction surfaces of shrouds of turbine blades made of titanium alloy are confirmed. [ABSTRACT FROM AUTHOR]

A computational technique for creating a wear-resistant coating on shrouds of turbine blades is developed from a heat-resistant alloy by laser cladding of a metal-ceramic coating. On basis of numerical simulation of heating and melting of a two-layer semi-bounded body with Stefan boundary conditions, the values of the heat flux and the time of its action during laser melting of the coating are determined. The distribution of temperature in the coating up to the moment of its fusing to the base is determined. The values of the heat flux for preservation of the strengthening phase of aluminum oxide in the coating are determined. The prospects of laser cladding of coatings containing particles of aluminum oxide for wear protection of friction surfaces of shrouds of turbine blades made of heat-resistant steel are confirmed. [ABSTRACT FROM AUTHOR]

The results of high-temperature tribological tests of carbon-containing materials during friction against 40X13 steel in the temperature range from plus 300 to plus 700 °C in atmospheric conditions. The modified friction surface of Argolon-2D material with copper oxide and polytetrafluoroethylene paired with 40X13 steel improves antifriction properties of the friction surface, reduces the value of the friction coefficient. The range of values of the friction coefficient at a temperature of +400 °C is 0.10 ... 0.14, and at a temperature of +500 °C is 0.15 ... 0.23. At a sliding speed of 0.16 m/s, a load of 0.5 MPa and a temperature of +500 °C, the friction coefficient of the modified friction surface is 58% lower than that of the untreated one. [ABSTRACT FROM AUTHOR]

The issues of the high-temperature tribological tests of carbon-containing materials during friction against 40X13 steel in the temperature range from plus 20 to plus 800 ° C in atmospheric conditions are studied in the article. As a result of the research, it is shown that the modified friction surface made of the Hardcarb-T material in selenium and polytetrafluoroethylene vapors improves the antifriction properties during tribological tests in a pair with a 40X13 counterbody steel. The spread of values of the coefficient of friction of the material "Hardcarb-T", treated in vapors of selenium and polytetrafluoroethylene, at a temperature of +500 ° C and a load of 1.0 MPa in the speed range 0.05-0.25 m / s is 0.22 ... 0, 26. At a sliding speed of 0.05 m / s, the friction coefficient of the treated surface is 45% less than that of the untreated one. [ABSTRACT FROM AUTHOR]

The article studied the issues of friction of a carbon-containing material with 40X13 steel at high temperatures in a carbon dioxide environment for use in friction units operating in the atmosphere of Venus. The influence of the sliding speed and the contact load is investigated. It is experimentally shown that the test environment in the form of carbon dioxide has a positive effect on the coefficient of friction in the direction of its reduction. At a temperature of 400...500 ° C, a load of 0.67 MPa and a speed of 0.05 m/s, the coefficient of friction is in the range of 0.13-0.19. [ABSTRACT FROM AUTHOR]