Chemistry of magnetic recording disk surfaces with intermittent asperity contacts

Since many of the newer disk drive products incorporate load/unload to avoi d starting and stopping on the disk surface, a new low-velocity accelerated life test was developed to simulate the tribology at ultra-low flying heig ht with asperity contacts, Surface chemical analysis of the tested regions detects Lubricant removal by desorption, and fragments with a carboxylic ac id end group and their organic amine salts. An increase in the water adsorp tion on the tested regions is attributed to the hydrophilic carboxylic acid groups.