Investigation of Lubricant Transfer between Slider and Disk Using Molecular Dynamics Simulation

A model for lubricant transfer from a rotating magnetic recording disk to a magnetic recording slider is developed using molecular dynamics simulation. The combined effect of disk velocity and local air-bearing pressure changes on lubricant transfer is investigated. The simulation results indicate that local pressure changes in the absence of disk circumferential velocity can cause lubricant redistribution on the disk, while local pressure changes on a moving disk can result in lubricant transfer from the disk to the slider. The amount of lubricant transferred from the disk to the slider and the lubricant buildup on the disk are a function of the local pressure change and disk velocity. The amount of lubricant transferred from the disk to the slider and the height of lubricant buildup on the disk surface decrease with an increase in the number of functional groups of the disk, a decrease in the local pressure change, and a decrease in the disk circumferential velocity.