the influence of the heat-shielding effect of oils on the occurrence of wear in mobile interfaces during jamming, characterized by such a defect as a bully and accompanied by the transfer of metal from one friction surface to another, is analyzed. The research was carried out both on the basis of theoretical calculations based on the thermodynamic theory of friction, and empirical tests using the developed device for simulating a temperature flash on a stationary friction contact and subsequent observation of the propagation of the heat flow according to the indications of thermocouples. On the basis of theoretical assumptions, and the results of the research, the hypothesis that the heat energy released as the result of frictional interactions at microscopic contact, has a high density and is spread with considerable speed mainly in the direction with the lowest thermal resistance due to the thermophysical characteristics of the material (density, conductivity) and thermal capacity, for example, thin boundary films (oil, oxide, servovite, sputtered, etc.) with a thickness of 1 µm and is comparable with the height of asperities. The results of the research confirm the hypothesis about the role of the heat-shielding effect of lubricants on the microcontact overheating and changes in the structure and properties of both the lubricant and the metal surface layer, which in turn cause increased wear of machine parts.
heat shielding effect, friction, surface, wear, bully
Введение
Даже при использовании самых современных смазочных материалов и технологий обработки металлов на рабочей поверхности деталей, работающих при относительно высоких скоростях и давлениях, наблюдаются в разной степени характерные повреждения – заедания. Такие дефекты поверхности возникают в результате явления местного соединения двух твердых тел, происходящего вследствие действия молекулярных сил при трении [1]. Издержки лесной отрасли, вызванные преждевременной заменой деталей машин, существенно сказываются на эффективности лесозаготовки [2].
1. GOST 27674-88 Trenie, iznashivanie i smazka. Terminy i opredeleniya. - M. : Izd-vo standartov, 1992. - 19 s.;
2. Kulakova, E. N. Sovershenstvovanie normativno-pravovogo i nauchno-metodicheskogo obespecheniya vosproizvodstva lesov / E. N. Kulakova, M. P. Chernyshov, S. I. Degtyareva. // Vestnik Moskovskogo gosudarstvennogo universiteta lesa - Lesnoy vestnik. - 2016. - T. 20. - №2. S. 106-111.
3. Chichinadze, A.V. Trenie, iznos i smazka (tribologiya i tribotehnika) / A. V. Chichinadze, E. M. Berliner, E. D. Braun i dr.; Pod obsch. red. A. V. Chichinadze. - M. : Mashinostroenie, 2003. - 576 s.; il..
4. Popov, D. A. Ustroystvo dlya issledovaniya teploekraniruyuschego deystviya granichnyh maslyanyh plenok / D. A. Popov, A. M. Kadyrmetov, A. S. Pustovalov // Sb. dokladov po itogam Mezhdunarodnoy tehnicheskoy konferencii «MEHTRIBOTRANS - 2016». - Rostov na Donu RGUPS - 2016. - t.1. - S. 223-227.
5. Popov, D. A. Analiticheskiy raschet temperatury na poverhnosti treniya s uchetom ekraniruyuschego deystviya tonkih granichnyh plenok [Tekst] / D. A. Popov, A. M. Kadyrmetov, V. V. Zaikin, A. Yu. Sinel'nikov // Aktual'nye napravleniya nauchnyh issledovaniy XXI veka : teoriya i praktika : sbornik nauchnyh trudov po materialam mezhdunarodnoy zaochnoy nauchno-prakticheskoy konferencii. - Voronezh, 2016. - № 5, ch. 4 (25-4) - S. 115-120.
6. Investigation of contact thermal resistance in a finite cylinder with an internal source by the fast expansion method and the problem of consistency of boundary conditions / A. D. Chernyshov, V. M. Popov, V. V. Goryainov, O. V. Leshonkov // Journal of engineering physics and thermophysics. - 2017. - Vol. 90, № 5. - P. 1225-1233. - DOI:https://doi.org/10.1007/s10891-017-1678-7. - Bibliogr.: s. 1233 (16 nazv.). - eLIBRARY.
7. Spravochnik po tribotehnike / pod red. M. Hembdy, A. V. Chichinadze - M. : Mashinostroenie. - 1992. - T.3. - 720 s.
