In disk drive technology, lubricant thickness and roughness are important, but often overlooked, contributors to slider–disk spacing. In this paper, we use X-ray reflectivity to measure the thickness and lubricant–air roughness of a perfluoropolyether lubricant (Fomblin Zdol) on silicon wafers and carbon overcoats. For Zdol on smooth silicon, the roughness increases with increasing lubricant th...

The properties of butane (C4H10) lubricants confined between two approaching solids are investigated by a model that accounts for the curvature and elastic properties of the solid surfaces. We consider the linear n-butane and the branched isobutane. For the linear molecule, well defined molecular layers develop in the lubricant film when the width is of the order of a few atomic diameters. The ...

This paper presents an investigation on the tribological properties of zinc borate ultrafine powder (ZBUP) employed as a lubricant additive in sunflower oil. The stable dispersions of 0.5 wt%, 1 wt% and 2 wt% ZBUP in sunflower oil were achieved by using an ultrasonic homogenizer. Both a 4-ball tester and a pin-on-disc tester were employed to evaluate the antiwear and friction reduction capabili...

The thermodynamic model of ultrathin lubricant lm melting conned between two atomically-at solid surfaces is built using the Landau phase transition approach. Non-equilibrium entropy is introduced describing the part of thermal motion conditioned by non-equilibrium and non-homogeneous character of the thermal distribution. The equilibrium entropy is changed during time due to transition of non-...

Zinc dialkyldithiophosphate additives are used to control wear and inhibit oxidation in almost all engine oils as well as many other types of lubricant. They limit wear primarily by forming a thick, protective, phosphate glass-based tribofilm on rubbing surfaces. This film formation can occur at low temperatures and is relatively indifferent to the chemical nature of the substrate. There has be...

A number of environmentally adapted lubricants have been proposed in response to the environmental and health impacts of metalworking fluids (MWFs). The alternatives typically substitute petroleum with vegetable-based components and/or deliver minimum quantities of lubricant in gas rather than water, with the former strategy being more prevalent than the latter. A comparative life cycle assessm...

Novel biosurfactant-producing strains were isolated from hydrocarboncontaminated environments that exclusively utilize agro-waste as their primary carbon source for the expression of biosurfactants. These were quantified using various standardized methods. Among the agro-waste screened, Beta vulgaris (Beetroot) proved to be the most suitable substrate, for which the biosurfactants produced by t...

Reducing the friction of liquid flows on solid surfaces has become an important issue with the development of microfluidics systems, and more generally for the manipulation of fluids at small scales. To achieve high slippage of liquids at walls, the use of gas as a lubricant--such as microbubbles trapped in superhydrophobic surfaces--has been suggested. The effect of microbubbles on the effecti...

Optimization of multi-criteria problems is a great need of producers to produce precision parts with low costs. Optimization of multi-performance characteristics is more complex compared to optimization of single-performance characteristics. The theory of grey system is a new technique for performing prediction, relational analysis, and decision making in many areas. In this paper, the use of g...

This paper explains the effect of various lubricant and engine temperatures on the intake mass air flow, engine noise and lubricant pressure behaviour of a motor-driven spark ignition engine. The lubricant pressure, engine noise and mass air flow changes were recorded under a steady state operating condition with an increased engine speed in which both the volume and temperature of the lubrican...