SIMULTANEOUS MEASUREMENT OF PIN WEAR AND CHANGE IN LUBRICANT THICKNESS ON THIN-FILM MAGNETIC DISKS

The relation between head wear and disk-lubricant thickness was studie d by transparent pin wear tests on thin-film magnetic disks while maki ng simultaneous micro-ellipsometer measurements to determine changes i n lubricant thickness, As-dipped and rinsed lubricant disks were prepa red to study the effects of free and adsorbed lubricants, On the rinse d disk without free lubricant, pin wear started after one minute of sl iding, and the decrease in lubricant thickness on the sliding track wa s small, On the as-dipped disk with free lubricant, pin wear started a fter 30 minutes of sliding, and was less pronounced than that on the r insed disk, while lubricant thickness decreased until wear started, an d became constant thereafter, The decrease in lubricant thickness was greater than that on the rinsed disk, Free lubricant was shown to redu ce pin Rear, The replenishment of lubricant was also measured, A model of pin wear and change in lubricant thickness is proposed taking into account disk-surface roughness and the replenishment of free lubrican t.