Lubricant transfer from disk to slider in hard disk drives

The physics behind lubricant transfer from disk to slider and lubricant accumulation on the slider in hard disk drives is explained. The effect of slider air bearing pressure on the lubricant transfer is discussed. It is found that the lubricant transfer is not affected by slider air bearing pressure. Lubricant molecular weight plays a dominant role in the lubricant transfer and lubricant accumulation. The amount of lubricant transfer and accumulation decreases dramatically with the increase in lubricant molecular weight. A thinner lubricant and higher bonding ratio of lubricant on disk surface reduce the lubricant transfer and accumulation obviously.