Izračun kontaktnih temperatur v fretinških razmerah
M. Kalin, J. Vižintin
Strojniški vestnik 47 (2001) 129–139.
AbstractObrabne in torne lastnosti površin v kontaktu so znatno odvisne od kontaktnih temperatur, zato je njihova določitev velikega pomena v vsaki tribološki uporabi. Številni modeli, ki so na voljo v literaturi, uporabljajo precej različne fizikalne, dinamične in geometrijske predpostavke. Posledica tega so velika razhajanja rezultatov za isti računski primer. Čeprav so ta dejstva splošno znana, so velikokrat pri izračunih spregledana. V predstavljenem prispevku smo analizirali vpliv lastnosti kontaktnih površin med jeklom in silicijevim nitridom v razmerah mejnega mazanja z oljem in nemazanih kontaktov. Predstavljeni so vplivi spremembe termičnih lastnosti koeficienta trenja in realne kontaktne površine na izračun kontaktnih temperatur. Za analizo smo uporabili deset različnih teoretičnih modelov. Rezultati kažejo velike razlike med posameznimi modeli in še posebej izjemen vpliv lastnosti kontaktnih površin na izračunane temperature.
The wear and friction properties of tribological interfaces are closely linked to the contact temperature and a knowledge of this temperature is of great interest for tribological applications. The many different temperature-calculation methods that are available in the literature are based on quite different psysical, dynamic and geometric assumptions. As a consequence, large disrepancies in the results can be obtained for the some contact conditions. Although this is a well-known fact, it is sometimes overlooked. In this paper the effects at a tribological interface between silicon nitride and steel under unlubricated and boundary-lubricated fretting conditions were studied. The effects of a change in the contact's thermal properties, as well as its coefficient of friction and the real contact area on the calculated flash temperature are presented. Ten different ready-to-use theoretical models were selected for the purposes of this investigation. The results show a significant difference between the various models, and in particular, the critical importance of the tribological interface properties on the calculated temperatures.
Keywords: temperatures, models, calculations, fretting