Viscosity, oxidative stability, deposit formation, volatility, lubricity and additive compatibility of castor oil (88+% ricinoleic) were compared to super-refined mineral oil (SRMO) and high oleic sunflower oil (HOSO). A satisfactory viscosity index (VI) of 90 and the extraordinarily high viscosity of castor oil can be related to hydrogen bonding of hydroxy monounsaturated triglycerides. When oxidized in thin film microoxidation test on a steel surface at 225°C under controlled air flow, castor oil showed deposit forming tendencies tower than HOSO but much higher than SRMO. Both vegetable oils had low volatility and demonstrated similar high molecular weight oxidation product formation tendencies at 175°C. Castor oil solubilized higher concentrations of antioxidants, but the oxidative stability of the formulation was lower when compared to HOSO. Without additives castor oil was comparable to other vegetable oils and superior to SRMO in performance on the four-ball wear tester.
|Original language||English (US)|
|Number of pages||6|
|Specialist publication||Lubrication Engineering|
|State||Published - Dec 1997|
All Science Journal Classification (ASJC) codes
- Industrial and Manufacturing Engineering