Experimental study of slider–lubricant interaction with different slider designs

Abstract

In this study, a new type of femto slider (Panda IV) with improved force arrangement and higher air pressure/higher stiffness at trailing edge of the slider was evaluated and compared experimentally with our previous type of femto sliders (Panda II and III). The evaluations were conducted on the Candela 5100 Optical Surface Analyzer (OSA) with the VENA CSS/load-unload system attached. Disks coated with a layer of 1.2 nm lubricant were specially prepared with a lubricant step for the comparison tests. Flying height (FH) of each slider was calibrated by bump disk with 3.5 nm bump height for maintaining the consistent FH during the tests. The relative amount of lubricant redistribution was analyzed with an OSA immediately after each slider is flown on-track for a period of time. It is found that the amount of lubricant transferred or the slider-lubricant interaction are minimized by reducing the size of slider's central trailing pad. Finally, possible explanations on the lubricant transfer are discussed.

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

“…学者们对磁头/磁盘之间润滑剂转移的数值研究 结果表明: 增加润滑剂分子的重量 [4] , 增加润滑剂的 吸附率 [5] , 提高润滑剂分子链的刚度 [6] 或减小润滑膜 的厚度 [5] 都可以减少磁头/磁盘之间的润滑剂转移. Man 等人 [7] 的研究结果表明磁头的空气轴承表面设 计会对磁头/磁盘之间的润滑剂转移产生影响. 当磁 头飞行高度在 3.5 nm 左右时, 磁头与磁盘之间的距 离接近润滑剂分子的平均自由程, 蒸发后的润滑剂 分子会附着并凝结在磁头表面.…”

“…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.…”