Elastic Contact and Friction Between Sliders and Circumferentially Textured Disks—Part II: Meniscus Force

Abstract

This series of three papers presents an experimental and numerical analysis of friction in a thin-film rigid disk with a circumferential surface texture, under various humidities. In Part II, we develop a theoretical formulation of the meniscus force of elliptical contact at isolated liquid bridges. This model predicts that the mean real pressure due to the meniscus force apparently decreases the net real contact pressure pr and increases the frictional coefficient. This effect becomes significant when the relative surface energy of the liquid 2γ/σ is comparable to pr , where σ is the standard deviation of asperity height distribution. When the disk is covered with lubricant and the liquid bridges are connected with each other, the solid noncontacting asperities play an important role in the formation of the meniscus force, and the relative lubricant thickness t/σ is the critical factor determining the friction.