磁盘润滑膜全氟聚醚的分子动力学模拟研究  

A molecular dynamics study on lubricant perfluoropolyether in hard disk driver

作　　者：李欣[1] 胡元中[1] 王慧[1] 

机构地区：[1]清华大学摩擦学国家重点实验室,北京100084

出　　处：《物理学报》2005年第8期3787-3792,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:50390060);国家重点基础研究发展规划(批准号:2003CB716201)资助的课题.~~

摘　　要：纳米润滑膜全氟聚醚(perfluoropolyether,简称PFPE)在固体表面的结构和迁移特性对于计算机磁盘磁头驱动系统的可靠性具有重要的作用.采用基于粗粒珠簧模型的分子动力学模拟方法,考察了不同壁面和端基极性对于PFPE膜静态特性(如分子构型、单体密度分布、端基密度分布)以及动态特性(如自扩散系数)的影响.静态特性的模拟结果表明,非极性PFPE膜在壁面附近具有单层厚度为一个单体直径的层状结构,而极性PFPE膜则具有复杂的层状结构.动态特性的模拟结果表明,PFPE膜的扩散能力因壁面作用而增强并因端基极性作用而减弱.The structure of nanoscale lubricant films perfluoropolyether (PFPE) and its mobility on a solid surface are important for the service durability and reliability of the computer head-disk device. Molecular dynamic simulations based on a coarse-grained bead-spring model are adopted to investigate the static properties such as molecular conformation, bead density, end bead density and the dynamic properties such as self-diffusion coefficient as a function of the wall effect and the functionality effect of PFPE films. The simulation results of static properties show that there is a monolayer in surface layer for nonpolar PFPE, while there is a complex layered structure for polar PFPE. While the simulation results of dynamic properties show that the diffusivity of PFPE films is enhanced by wall effect but decreased by the functionality effect.

关 键 词：分子动力学 全氟聚醚 润滑膜 模拟研究 静态特性 密度分布 模拟结果 动态特性 层状结构 计算机磁盘 自扩散系数 PE膜 模拟方法 驱动系统 迁移特性 固体表面 分子构型 扩散能力 PF 可靠性 端基 壁面 非极性 单体 粗粒 

分 类 号：TH117.2[机械工程—机械设计及理论]