A model for lubricant flow from disk to slider

Abstract

vressure 1. 1 tends to retain lubricant on the disk (rccond term). The condcnsation rate R,,,,,,, can A MODEL FOR LUBRICANT FLOW FROM DISK TO SLIDER

The Effect of UV Irradiation on the Z-Tetraol Boundary Lubricant

“…While the slider body flies approximately 8-9 nm above the disk surface, the clearance between the read-write element of the slider and the disk surface is actually as little as several nm due to pole tip protrusion during read/write operations. At these small spacings, the combined effects of the air shear stress, the air bearing pressure, and the van der Waals attractive forces operating between the slider and the disk surfaces can cause lubricant disturbance on the disk surface [1][2][3]. Isolated and/or periodic lubricant moguls and ripples that form on the disk surface can increase the probability of lubricant transfer to the slider leading to flying instability.…”

Effect of surface topography of disk on lubricant distribution and lubricant transfer between disk and slider

“…总结前人的研究发现 [4,7,11] , 磁盘表面的润滑剂 蒸发后在磁头表面凝结是导致润滑剂转移的一个原 因. 但是随着磁头飞行高度的降低, 磁头在磁盘表面 飞行时, 是否存在其他原因导致润滑剂在磁头/磁盘 界面转移仍需要进一步研究.…”

Interface stability study towards ultra-high density magnetic recording

“…The mean free path of air at 1 atm of atmospheric pressure is 63.5 nm. Since the slider-disk spacing is smaller than the mean free path of air, the volumetric flow rates of lubricant on slider Q cond and Q evap can thus be expressed as [43,44] ( ) shows that even though INSIC slider has a larger flying height (6.72 nm) than Panda III slider (5.83 nm), the larger effective slider area of INSIC slider can still displaced 55 % more lubricant across the disk surface than the Panda III slider which has a smaller effective slider area. As mentioned earlier in chapter 5.4, when a higher flying height slider is compared with a lower flying height slider, because of weaker slider-lubricant interaction for the higher flying height slider, it will transfer less lubricant.…”

“…At steady state, the inflow of lubricant to the slider-disk interface will be equal to the outflow from the slider-disk interface. Thus lubricant transfer's component of the slider can be expressed as[43]…”

“…of lubricant on slider surface due to shearing effect associated with slider can be expressed as[43,44] 4a) and the volumetric flowrate of lubricant on disk surface due to shearing effect associated with slider can be expressed as t d and t s are the lubricant thickness on disk and slider surface respectively, η a is the air viscosity, η ls is lube effective surface viscosity on slider surface, Π(t) is the disjoining pressure for lubricant thickness t, A is effective slider area, ρ is lubricant density, T is the absolute temperature, P 0 is bulk vapor pressure, M n is molecular weight, and R is the gas constant. The effective slider area A is roughly equal to the product of a and b, as illustrated inFig.…”