头/盘界面对润滑剂转移行为及分布的影响

为进一步提高磁头飞行的稳定性,增加硬盘存储容量,采用分子动力学方法研究磁头磁盘接触条件下盘片上类金刚石薄膜(DLC)层粗糙度、DLC表层官能团比例及单个润滑剂分子中羟基数对润滑剂转移行为及润滑剂在盘片表面分布的影响.研究结果表明:降低DLC层粗糙度,增加DLC表层官能团比例都将降低磁头磁盘间的润滑剂转移量;当磁盘表面存在物理吸附态的润滑剂分子时,增加单个润滑剂分子中的羟基数也可降低润滑剂转移量;但降低DLC层粗糙度或同时增加DLC表层官能团的比例和单个润滑剂中羟基数会增加润滑剂在盘片表面堆积的高度,进而降低磁头飞行稳定性.综合考虑润滑剂转移量和润滑剂在磁盘表面堆积厚度对磁头飞行稳定性的影响,DLC层粗糙度应降低至约0.07 nm,DLC表层官能团比例增至约80%,单个润滑剂分子中的羟基数量应少于8个.

Effect of head/disk interface on lubricant transfer behavior and lubricant distribution

To further increase the slider flying stability, thereby enhancing capacity of hard disk drives, the effects of DLC (diamond like carbon) layer roughness, function group ratio and the number of hydroxyl within one lubricant molecule on lubricant transfer and lubricant distribution on the disk surface are investigated by molecular dynamics simulation, and the results indicate that the lubricant transfer behavior can be improved by decreasing DLC layer roughness or increasing functional group ratio. The lubricant transfer can also be improved by increasing the number of hydroxyl within one lubricant molecule, when physically absorbed lubricant exists on the disk surface. However, the lubricant accumulation height on the disk surface can be increased by decreasing DLC layer roughness or increasing function group ratio on the DLC surface and hydroxyl number within one lubricant molecule simultaneously, resulting in the decreasing of slider flying stability. Therefore, considering the effects of lubricant transfer volume and the thickness of lubricant accumulation on the disk surface, it is better to decrease the DLC layer roughness to approximately 0.07 nm, increase the functional group ratio to about 80% and make the number of hydroxyl within one lubricant molecule less than eight.