Theoretical modeling of surface texturing in hydrodynamic lubrication is a necessary first step to obtain favorable effect of the texturing. This invited review presents a comprehensive summary of the modeling of several basic applications that was done mostly by the author’s group at Technion and published in the relevant literature.

Diamond-like carbon (DLC) coatings are known to provide beneficial mechanical and tribological properties in harsh environments. Their combination of high wear resistance and low friction has led to their extensive use in any number of industries. The tribological performance of a DLC coating is varied however, and the frictional response is known to be strongly dependent on the surrounding environment, as well as the material composition and bonding structure of the DLC coating. This paper p...

Two lithium-based ionic liquids (ILs, L-C3N3, and L-P3N3) were synthesized and evaluated as novel lubricant additives for multiply alkylated cyclopentanes (MACs). They were found to be approximately 1.0% soluble in MACs at room temperature (RT), whereas traditional ILs, such as 1-ethyl-3-methylimidazolium tetrafluoroborate (L-B102), 1-hexyl-3-methylimidazolium hexafluorophosphate (L-P106), and 1-ethyl-3- methylimidazolium bis(trifluoromethylsulfonyl)imide (L-F102), could not be dissolved in t...

This work is aimed at investigating the friction and wear performance of different polymeric materials having potential for hydraulic system components under lubricated sliding conditions against a steel counter face. A pin-on-disc test configuration was used for the experimental study. The different polymeric materials selected for these studies were commercial polyimides (PI), polyether ether ketone (PEEK), and flouropolymers. Some of these materials were bulk materials whereas others were ...

Even though the slipperiness of ice is important both technologically and environmentally and often experienced in everyday life, the nanoscale processes determining ice friction are still unclear. We study the friction of a smooth ice–ice interface using atomistic simulations, and especially consider the effects of temperature, load, and sliding velocity. At this scale, frictional behavior is seen to be determined by the lubricating effect of a liquid premelt layer between the sliding ice sh...

This paper investigates the effect of unsaturated fatty acid additives on the lubricating properties of a biodiesel, composed of a blend of fatty acid methyl esters (FAMEs) and a conventional diesel fuel. The presence of fatty acids as additives for biodiesel improves their lubricating properties at elevated temperature conditions. The formation of a protective lubricating tribochemical film on the steel contact surfaces has been evidenced. Elevated temperature conditions and possibly oxygen ...

Using special testers, the triboelectric behaviors of several materials were investigated in this paper under the conditions of high speeds and large currents. The obtained results revealed that the tribological behaviors and current-conducting characteristics have complicated interrelationships. Worsening in the servicing conditions can obviously deteriorate the tribological as well as electrical behaviors; high sliding speeds and large electrical currents can worsen the tribological and ele...

To reduce their fuel related logistic burden, North Atlantic Treaty Organization (NATO) Armed Forces are advancing the use of a single fuel for both aircraft and ground equipment. To this end, F-34 (the commercial equivalent is Jet A-1) is replacing distillate diesel fuel in many applications. However, tests conducted with this kerosene type on high frequency reciprocating rig showed that this type of fuel causes unacceptable wear. This excessive wear is caused by the poor lubricity of aviati...