Design of Negative Pressure Slider for Magnetic Recording Disks

Abstract

This paper reports on investigations of static and dynamic characteristics of a negative pressure slider for magnetic recording disks. The negative pressure slider is composed of two narrow pressure pads, as on a cylindrical slider, separated by a rather large reverse step region. Through a modified Reynolds equation, which considers slip flow effects, the static and dynamic pressure distributions are calculated by divergence formulation and a finite difference method. Using the calculated results, the optimum reverse step depth is clarified in terms of both dynamic characteristics and wear caused by starting and stopping in contact with the disk. With a 4.6 mm length, 3.2 mm total pad width and 4 μm reverse step depth, the negative pressure slider has six times the air film stiffness of a conventional light load slider. Experimental data concerning spacing versus reverse step depth and take-off characteristics for the negative pressure slider in submicron spacing region are in good agreement with the calculated results.