As the application of low-viscosity oil progresses to reduce friction losses in IC engines, the increases of friction, wear and scuffing are concerned for the sliding surfaces in tribo-components. According to the physical and chemical properties of interface materials and lubricants, the analytical study on thermal friction characteristics of the boundary lubrication has been conducted to investigate the effect of temperature on the function of oil additives as friction modifies and/or anti-scuffing agents. Three base oils with low viscosities, three extreme pressure anti-wear agents and two organo-molybdenum friction modifiers were used to measure friction changes with a cam/follower test apparatus. The functional sensitivity of additives in low-viscosity oils is considered by analyzing relationships between friction and temperature in the running-in process of interfaces. The analysis is based on physicochemical properties such that all of the oil viscosity, the adsorption of oil molecules, the chemical reaction of oil additives forming the tribo-film low in shear stress and the strength of interface materials are due to the exponential function of the temperature just like the Arrhenius’ equation. From the analysis it has been found that the frictional shear stress depends on the involvement intensity of surface temperature in influences of oil viscosity, molecular adsorption / desorption and tribo-film formation for each term of running-in.
|Number of pages||50|
|Journal||Toraibarojisuto/Journal of Japanese Society of Tribologists|
|Publication status||Published - Jan 15 1994|