S1107-1-1 固化潤滑油およびグリースの超高圧レオロジー特性新評価法([S1107-1]トライボロジーにおける実験・計測・解析手法の新展開)

抄録

High-pressure rheological properties of solidified lubricant oils and greases were evaluated by an originally proposed new method, that is, the large plastic deformation analysis of metal microspheres (about 0.07 mm) in these lubricants, occurring due to non-hydrostatic pressurization of a diamond-anvil pressure cell. The solidification pressures obtained by observing aluminum sphere deformation were 0.2-0.7 GPa for traction grease and oils, 1.3-1.8 GPa for synthetic base oils and their urea or lithium greases including ionic liquid and recent aerospace lubricants. The solidification pressures were almost the same values among base oils and their greases. By substituting the solidification pressures and pressure-viscosity coefficients in the Barus equation, viscosities at the solidification pressure were obtained. The values were different for each oil and were within the order of 10^4〜10^7 Pas. Based on several assumptions, rough equivalent traction coefficients of the solidified oils could be estimated up to 4 GPa.