Theoretical Model for Lubricant Pick-Up (Breakage of Liquid Meniscus Bridge Due to Elongation in Bridged Direction)

In recent magnetic storage systems, the spacing between the flying head and the disk has been drastically decreased to less than 5 nm in order to realize ultra-high density recording. Lubricant on the disk is picked up on the flying head slider as a result of the intermittent contact between the slider and the disk, or due to condensation of the lubricant vapor. In this study, the basic characteristics of lubricant pick-up caused by the breakage of a liquid meniscus bridge are investigated theoretically. A model for the breakage of a liquid meniscus bridge is proposed and the volume fraction of the lubricant pick-up is derived. The effects of the radius of curvature of a sphere surface and the initial volume of a liquid droplet on the volume fraction of the lubricant pick-up are discussed. The theoretical results obtained from a model that the authors proposed showed good agreement with the experimental results. This model is considered to be useful in the prediction of lubricant pick-up characteristics.