Relationship of Adhesion/Friction Forces and Slider Vibration in Surfing-Recording HDI System

Abstract

In this study, the friction forces between a slider and disk surface with different lubricant thicknesses were measured at touchdown. Touchdown measurements of the friction and adhesion forces on a disk were made using a pin-on-disk tribotester. The friction force at touchdown could not be explained by a monotonic behavior, where the friction force gradually decreased with the lubricant thickness. Based on a comparison of the results measured using the pin-on-disk tribotester, it was estimated that the optimal adhesion force and a lower friction force are needed for the surfing regime at touchdown.Index Terms-Dynamic flying height (DFH), hard disk drive, head-disk interface, magnetic disk, pin-on-disk test.

Investigation of electrostatically tunable adhesion and instability of flying head slider

“…However, it could jump to another value in the former adhesion numerical calculation model of Ref. [4] even everything about affecting the F s has not changed at that time, which is against with the results of experiments and simulations [8,26]. Here, the limitation is solved in our proposed model.…”

“…Equation ( 6) is applicable to a quasi-static process; however, the sider oscillates on the rotating disk when it is working. From the experiment measure of pull-in and pull-off forces implemented by Tani et al [26], the capillary adhesion also exists at the nanoscale. So, this lubricant adhesion difference should be considered in the dynamic model during falling and rising, i.e., the difference between the height of liquid bridge formation and the height of liquid bridge breaks.…”

Thermal Behavior of Frictional Properties on Ultra-Thin Perfluoropolyether Lubricant Film

“…Therefore, the following analysis was performed using the relationship between the load and the frictional force. The contact between a plane and spherical surfaces has been discussed at length in the Johnson-Kendall-Roberts (JKR) theory [8,[11][12][13] considering the force of adhesion. If the load is, W 0 the adhesive force acting between the spherical and plane surfaces is W a , the radius of curvature of the spherical surface is R, and the adhesive energy between the spherical and plane surfaces is γ.…”

“…The method used to measure the frictional force is shown in Fig. 2 [8]. When the spindle motor was rotated, there was a run-out, i. e., an up-and-down movement of the disk surface, of approximately a few 10 μm during one revolution, which was due to the undulations of the spindle hub surface.…”

“…The piezo stage was further lowered, and when the maximum value of the load was in the range of 0.5-1.0 mN, the descent of the piezo stage was stopped while continuing the rotation of the disc. The contact area of the glass pin and the disk surface was heated by laser-beam irradiation, and the frictional force and load by developed pin-on-disk tester [8] were measured. The friction test was carried out at an ambient temperature of 23-26°C and a relative humidity of 30-32%.…”