ヤナギサワ　ケンジ   Kenji Yanagisawa   柳澤　憲史    所属   追手門学院大学  理工学部 機械工学科    職種   准教授
言語種別	英語
発行・発表の年月	2010/10
形態種別	論文
査読	査読あり
標題	Thickness Change in Molecularly Thin Lubricant Under Flying Head in Hard Disk Drives
執筆形態	代表編著
掲載誌名	TRIBOLOGY LETTERS
掲載区分	国外
出版社・発行元	SPRINGER/PLENUM PUBLISHERS
巻・号・頁	40(1),pp.99-103
担当区分	筆頭著者
著者・共著者	K. Yanagisawa,T. Watanabe,Y. Kawakubo,M. Yoshino
概要	In hard disk drives (HDDs), lubricants on disks are very important material to reduce head and disk wear. Thus, it is necessary to know changes in lubricant thickness to keep lubricant thickness constant on rotating disks. For this purpose, we have to know changes in lubricant thickness during HDD operations. We developed a simulation program to simulate changes in lubricant thickness during HDD operations numerically. First, we had simulated the changes in lubricant thickness of 10-nm-thick non-polar lubricant film under a flying head. The result corresponded to a reported experimental result. In recent HDDs, a lubricant thickness has become molecularly thin and lubricants with polar end groups have been used. In molecularly thin polar lubricants, diffusion depends on their thickness and their viscosity becomes very high. Next, we simulated the change in the lubricant thickness of 2-nm-thick polar lubricant film considering the effects of lubricant initial thickness. The simulated results showed that the changes were very small in 2-nm-thick lubricant film, but they were not confirmed with the experiment. In this paper, experimental results of the change in the thickness of molecularly thin non-polar and polar lubricants under a flying head were first measured. The simulations that took account of thickness-dependent diffusion and thin-film viscosity were then performed with the simulation parameters based on the experiments. The simulated results of lubricant distribution were in good agreement with the experimental results.
DOI	10.1007/s11249-010-9642-0
ISSN	1023-8883