Cheng Qilong, Rajauria Sukumar, Schreck Erhard, Smith Robert, Dai Qing, Bogy David B
Computer Mechanics Laboratory, University of California at Berkeley, Berkeley, CA, USA.
Western Digital Corporation, Recording Sub System Staging and Research, San Jose, CA, USA.
Commun Eng. 2024 Oct 5;3(1):138. doi: 10.1038/s44172-024-00284-3.
Laser-lubricant interaction has been a critical reliability issue in a thermo-tribological system named heat-assisted magnetic recording, one of the next generation hard disk drive solutions to increasing data storage. The lubricant response under laser irradiation and the subsequent lubricant recovery are crucial to the system's reliability and longevity, however, they cannot be diagnosed locally and timely so far. Here, we propose a thermal scheme to in-situ characterize the mechanical laser-lubricant interaction. The nanometer-thick lubricant has a thermal barrier effect on the near-field thermal transport in the system, according to which the lubricant thickness can be determined. As demonstrations, this paper reports the first quantitative in-situ measurements of the laser-induced lubricant depletion and the subsequent reflow dynamics. The proposed scheme shows a sub-angstrom resolution (~0.2 Å) and a fast response time within seconds, rendering in-situ real-time lubricant diagnosis feasible in the practical hard disk drive products.
在一种名为热辅助磁记录的热摩擦学系统中，激光与润滑剂的相互作用一直是一个关键的可靠性问题，热辅助磁记录是下一代用于增加数据存储的硬盘驱动器解决方案之一。激光辐照下润滑剂的响应以及随后的润滑剂恢复对系统的可靠性和寿命至关重要，然而，到目前为止，它们还无法进行局部和及时的诊断。在此，我们提出一种热方案来原位表征激光与润滑剂的机械相互作用。纳米厚的润滑剂对系统中的近场热传输具有热障效应，据此可以确定润滑剂的厚度。作为示例，本文报告了激光诱导的润滑剂损耗以及随后的回流动力学的首次定量原位测量。所提出的方案显示出亚埃分辨率（约0.2 Å）和数秒内的快速响应时间，使得在实际硬盘驱动器产品中进行原位实时润滑剂诊断成为可能。
