Influence of physical states of amide type gel-lubricants on their tribological and rheological properties
Keywords:
gel-lubricant, low friction, lubricants, rheologyAbstract
The authors studied how changes in the physical states of amide type Gel-Lubricants (Gel-Lubes) affect their tribological and rheological properties. In the hydrodynamic lubrication region, viscosity varied dramatically around the melting point of Gel-Lube. Compared to a base oil, lower traction coefficients were observed in EHL with Gel-Lube in both the gel and liquid states. Friction coefficients under boundary lubrication conditions were lower than those of the base oil and a conventional grease, while much lower friction properties were obtained with Gel-Lube in a liquid state. Bearing friction torque measured in the liquid state was lower than that in the gel state. Results suggest that the viscosity reduction caused by changes in the physical state of Gel-Lube enable it to spread over the friction surfaces more easily and that the boundary film, composed of an adsorption layer of aliphatic amides, remains unchanged in both the gel and liquid states.