The Gas Bearing Interface of Opposed Recording Heads in a Disk Drive Utilizing Helium and Thin Titanium Foil Disks

Abstract

Increased storage capacity and decreased power consumption are two key motivations in the development of hard disk drive (HDD) storage products. Two ideas that address these areas have recently received attention in the literature. These are (1) the use of helium instead of air as the working gas in the drive and (2) the incorporation of a thin metal foil as the disk substrate, replacing the much thicker aluminum or glass substrate of the hard disk (HD). The work that has been previously reported considered either the use of helium or thin foil substrates, but not both. This paper does consider both. It reports dynamic gas bearing simulation results for the helium filled interface between opposed recording heads and a disk whose substrate is a thin titanium foil. Motivation for the selection of titanium as the foil material is described in the paper. The thickness of the foil is chosen so as to achieve an optimal combination of centrifugal force and bending force that will provide required disk flatness and stability during high-speed rotation. Large-scale dynamic simulation is used to track the response of the recording head slider-foil disk interface due to mechanical shock in the vertical, pitch, and roll directions. Results are described and compared with those of the configuration that includes helium and a HD. Attention is focused on response to off-design conditions that can create head crash with the HD.