MoP-2 CHANGE OF FLOW CHARACTERISTICS OF LIQUID NANO-STEP DUE TO HEATING

抄録

In the head-disk interface (HDI) of a hard disk drive (HDD), the effects of lubricant deformation on the flying characteristics of a head slider increase as the flying height decreases. Therefore, it is very important to investigate the deformation and flow characteristics of lubricant on a recording disk. In particular, in heat-assisted magnetic recording (HAMR), laser heating of the lubricant induces surface tension distribution and evaporation of lubricant, which may cause deformation of the lubricant film. In this study, flow characteristics of a liquid nano-step of perfluoropolyether (PFPE) on a solid substrate were investigated experimentally. Two types of PFPE lubricants (Z03 and Z-dol) were evaluated. Using the modified Boltzmann-Matano method, diffusion coefficients of the liquid nano-step, which shows the flow characteristics, were calculated from experimental data. As a result, change of flow characteristics of the liquid nano-step due to heating were clarified.