Simulation of Hydrocarbon Oil Contamination at the Head-Disk Interface Using Molecular Dynamics

摘要

Current hard disk drives use hydrocarbon-based oils to lubricate the actuator arm pivot and the fluid dynamic bearing spindle motor. At elevated drive temperatures, hydrocarbon oil molecules escape from the fluid dynamic bearing motor and pivot actuator by evaporation and aerosoling, entering into the drive air stream, and contaminating the head-disk interface. In this paper, we study the transfer mechanism of hydrocarbon molecules (n-alkane: C24H50 and C36H74) and disk lubricant (Zdol-PFPE) molecules at the head-disk interface using molecular dynamics simulation. A "two-step" transfer mechanism is postulated: Airborne hydrocarbon molecules condense first onto the disk surface and then transfer by evaporation to the slider surface. The numerical results obtained are in agreement with the assumed hypothesis of the transfer mechanism.