Трение и износ, 1997, Vol.18, No.1

Трение и износ, 1997, Vol.18, No.1

ТРЕНИЕ И ИЗНОС
Международный научный журнал
Published by INFOTRIBO Ltd., Gomel, Belarus

Том 18, номер 1; январь-февраль, 1997

СОДЕРЖАНИЕ

СТАТЬИ

Goryacheva I. G., Makhovskaya Yu. Yu.
Influence of surface layer imperfect elasticity on contact characteristics in sliding of rough elastic bodies. pp. 5--12
Summary: The analytical model is proposed to investigate the combined effect of surface roughness and mechanical nonhomogeneity in sliding contact of two elastic bodies. The surface roughness is modeled by a periodic system of cylindrical asperities. The mechanical nonhomogeneity of counterbody is taken into account by a viscoelastic layer bonded to an elastic half-plane. Two-dimensional contact problem is reduced to the integro-differential equation to determine the contact pressure. The results are used to analyze the influence of mechanical and geometrical properties of surface layer and roughness on contact characteristics and mechanical component of friction coefficient.

Zharov I. A.
Scale effects produced by abrasive wear. pp. 13--18
Summary: The scale factor has been used to derive formulas for rating wear by free and fixed abrasive particles. Specifically a relationship is derived between the wear rate, the distance between contacting surfaces and as the function of sizes of abrasive particles.

Rafeenko E. D., Chigarev A. V.
Mathematical modelling of surfaces with specified geometrical properties. pp. 19--24
Summary: The mathematical modelling of specified geometrical surfaces is based on time-independent constants. Hence, the wear is governed only by the velocity of machining reducing the mathematical problem to a combined solution of integral equations becoming equivalent to a single integral equation of Fredholm of the 1st order. The regularization method of Tikhonov has been applied to solve the resulting incorrect problem and investigate the effect of the parameters upon the obtained solutions. It has been established that the method of soft regularization is more suitable for the task.

Sergeev S. I.
Prediction of stiffness and damping of gasostatic bearings. pp. 25--29
Summary: Externally pressurized gas bearing with the slightly loaded, rotating and vibrating journal is considered. Using flow rate balance and Reynolds equations, the method far the calculation of the gas stiffness and damping is developed. It is found damping and stiffness are mutually interconnected. The increasing of the stiffness due to the rise of external pressure may reduce the damping to 10%, more often to 25% of its nominal value. So the compromise in stiffness and damping is required. In real machines there may be different sources of damping and excitation of vibrations comparable with that in the journal bearings. Some recommendations for the due design of pressurized gas journal bearings are suggested.

Grigoryev B. S.
Optimization of slider bearing by criterion of maximum stiffness. pp. 30--34
Summary: The shape of the lubricating film that provides the plane (one dimensional) slider bearing with maximum stiffness is obtained. Calculus of variations is used to do this. The stiffness of the bearing with the obtained film shape exceeds that of the bearing with maximum loading capacity approximately by 23% when their static load is the same.

Kharlamov V. V., Kolmogorov V. L., Pavlyshko S. V.
Unstable sliding friction under heavy loads. pp. 35--41
Summary: A mathematical model of the unstable friction and wear is based on a concept of the microgeometry of contacting surfaces and an assumption of a rather hard pin and a soft insert making the latter perfectly plastic and creating lubrication in the porous space between the rubbing surfaces. A system of relationships, algorithms and their solutions, test results based on relevant software are demonstrated.

Zavistovskii V. Ye., Bogdanova E. A., Zavistovskii S. Ye.
Structural and diffusional mechanism of healing wear microcracks. pp. 42--45
Summary: A mathematical model is advanced describing the mechanism of healing the micropores appearing during cracking in solid body under equilibrium conditions. It takes account crack radius, temperature and structural features of material.

Nazarov A. D.
Improvement of life and vibroacoustic behavior of engines by rating total unbalanced mass of piston and crank parts. pp. 46--52
Summary: A technique is advanced to rate the permissible total unbalanced mass due to deviations from the nominal one because of contamination of pistons, rings and crankpins. The life and vibroacoustic parameters of crankpin bearings allows to determine the critical level of wear for 4.25 1 V-8 engines. This analysis allows to extend life during manufacture and reconditioning, to reduce the probability of failures, vibration and noise of engines.

Gromakovskii D. G.
System and structure of wear concepts. pp. 53--62
Summary: The problem is discussed how to systemize and classify the tribological concepts, terms and models based on the systems analysis and to emphasize the advantages of the kinematic approach to the wear modelling.

Cherskii I. N., Starostin N. P.
Modelling friction and wear and development of diagnosis of metal-polymer units. pp. 63--73
Summary: The problems are outlined relating to a comprehensive approach to modelling friction and wear. It is proposed to summarize the earlier developed method of temperature diagnosis of sliding bearings for reconstruction of friction mode.

Ivanova V. S., Bushe N. A., Gershman I. S.
Structural adaptability as a process of self-organization in friction. pp. 74--79
Summary: The structural adaptability in friction is evaluated from the point of view of self-organization based on non-equilibrium phase transitions in secondary structures and their governing parameters. It is shown that the temperature of spontaneous heating can be included in these parameters.

Ershov B. I., Andrianov D. N.
Optimization of the sliding bearing surface shape. pp. 80--83
Summary: The piston group with its bearings is one of the most vulnerable parts in a hydrostatic power drive. The bearing surface shape should be optimized in order to extend its life and reduce production cost.

Chichinadze A. V., Polyakov N. V., Zemskov Yu. P., Klyuchnikov V. I.
Problem of evaluating heating intensity and wear resistance of discs in hydromechanical transmissions of passenger cars. pp. 84--88
Summary: It is proposed to replace common materials ill friction couples of hydromechanical transmissions with deposited layers, because the comparative rating of the heating intensity and tests have manifested effectiveness of such replacement increasing the service life 1.7--2.3 times.

Lavrinenko V. I., Ryzhov Ye. V., Solod V. Yu.
Contact of polishing wheel and blank material at electrical grinding. pp. 89--91
Summary: Friction is studied of a grinding wheel against blank under conditions of current passage through their contact. Relationship between friction coefficient and contact voltage drop for various types of materials have been analyzed to identify the range within which the "lubrication by current" occurs.

Chashechkina Zh. Yu., Orlov D. B., Tsyklin Yu. M., Anisimov V. S.
Characteristics of a bimetallic strip and sliding bearings with an antifriction layer of the Al--Pb alloy. pp. 92--96
Summary: The possibility to produce a bimetallic strip and sliding bearings with an antifriction layer of the experimental Al--Pb alloys has been studied. Their technologic and operating characteristics have been determined in comparison with the analogous properties of commercial products of AO20-1 and AO6-1 alloys. It has been shown that the technologic characteristics of the bimetallic strip with an antifriction Al--Pb layer comply with technical production requirements. It has been found that the operating characteristics of the bearings produced from the experimental Al--Pb alloys is higher against those from commercial AO6-1 (with coating) and AO20-1 alloys. The bearings produced from experimental alloys Al--10%Pb--10%Sn--l%Cu and Al--10%Pb--10%Sn--3%Cu the ingots of which were subjected to intermediate annealing at the bimetal production stage exhibit highest serviceability.

Yashcheritsyn P. I., Kozhuro L. M., Feldshtein E. Ye.
Wear resistance of coatings produced by electromagnetic surfacing. pp. 97--101
Summary: It is demonstrated that the composition of a coating allows to optimize the conditions of finishing a workpiece by using the processing data.

Sviridenok A. I., Sechko A. Ye.
Ecologically clean wear-resistant materials for interior of vehicles. pp. 102--107
Summary: The interiors of vehicles, planes and ships is commonly made of thermally-formed materials, such as fabrics, needle-fixed materials and textiles. These materials are made wear-resistant using various binders, such as latex, phenol formaldehyde and other resins which are basically ecologically unsafe both in production and in use. The paper describes the behavior of interior materials fabricated with the help of ecologically-safe thermoplastic binders adding strength and wear resistance to composites.

Mashkov Yu, K.
Temperature effects upon the structure and tribological behavior of filled PTFE. pp. 108--113
Summary: The results of experimentation show how the environment temperature affects the structure and the tribological behavior of filled PTFE manifesting that introduction of variously shaped fillers and temperature variations modify the supermolecular structure and the polymer crystallinity. It has been established that a certain external energy input into the surface layer produces a laminar structure of the polymer matrix which reduces friction and increases wear resistance of a composite.

Okhlopkova A. A., Vinogradov A. V., Krasnov A. P., Ustych Yu. N.
Tribochemical processes in filled PTFE. pp. 114--120
Summary: Tribochemical processes in composite materials based on ptfe in response to the chemical nature and the concentration of a filler have been investigated manifesting that introduction of dispersed particles induces profound modifications improving the structure and wear resistance.

Potekha V. L., Shcherek M. M., Kholodilov O. V.
Tribological dilatometry: the main terms & definitions. pp. 121--124
Summary: The analysis is presented of methodological basis for wear monitoring of tribosystem members by varying their linear dimensions with account for heat expansion. A system of terms and definitions is offered that characterized the new direction in tribodiagnostics.

Gorban V. F., Sychov V. V.
Comparative characteristics of wear of chromium galvanic and gas-thermal coatings. pp. 125--128
Summary: Wear of chromium gas-thermal and electrolytic coatings in response to velocity, load and conditions of lubrication has been investigated. It is demonstrated that gas-thermal coatings are superior to electrolytic ones, specifically for severe conditions of operation. The structure of such coatings has been studied showing that gas-thermal coatings manifest more traces of plastic deformation.

Ravin A. N., Volochko A. T., Laskovnev A. P.
Effectiveness of standardization of energy-saving materials and technologies (an example of the state standard for antifriction aluminum alloys). pp. 129--131
Summary: Novel antifriction aluminium alloys with powder fillers have been developed to replace bronze. A state standard is developed which determines their brands, technical specifications, production processes, raw materials and quality tests.

ЛЮДИ НАУКИ

Sergei M. Zakharov (To 60th anniversary). pp. 132--133.

КАЛЕНДАРЬ КОНФЕРЕНЦИЙ. pp. 134--135.

/ Издания академии / Научные журналы / К началу страницы