Molecular Mean Free Path Effects in Gas Lubricated Slider Bearings : 2nd Report, Experimental Studies

Abstract

The latest magnetic disk files require lightly loaded air-lubricated slider bearings operating with film thicknesses less than 0.5μm to achieve high recording density. This paper reports results on flying characteristics obtained from experiments with such air bearings, which are influenced considerably by slip-flow effects. Experiments are carried out in the range of 30 to 70% load reductions due to slip-flow. White light interferometric techniques for measuring the spacing between a rotating glass disk and the slider are improved. For load reductions less than 60%, experimental data agree well with the numerical solution of a modified Reynolds equation which takes into account the velocity-slip boundary conditions. It is verified that the modified Reynolds equation can be used to predict the static behavior of slider bearings in designing magnetic flying heads. An effective calculation technique for the Reynolds equation by the finite element method is presented.