Study on Lubricant Materials Transfer between Head and Disk

With the increase of hard disk storage density, the flying height of magnetic head sliders has become lower in recent years, which makes it easier for lubricant materials to transfer between the magnetic head and disk. The ability for lubricant materials to transfer is not only related to the operating conditions of disk but also related to the types of lubricant materials (Perfluoropolyether, PFPE) and diamond-like carbon (DLC) coating applied to the disk. Based on the principle of molecular dynamics, this study established the adsorption models on disks with different carbon content and the diffusion models of several common PFPE molecules in air. Besides, the adsorption energy and the diffusion coefficients of different models were calculated. Furthermore, the molecular weight, the molecular structure, the lubricant material's end functional groups, and the disk's carbon content were found to have influence on the transfer ability of lubricant materials.In particular, the latter two factors have further influence.