Normal and Shear Stresses in Dynamic, Submicron Liquid Bridges

[200681]本项目是一项为期3年的摩擦接触中毛细效应的实验和理论研究。提出的研究的动机是越来越小的形状因素的技术趋势，导致更高的表面积体积比和液体介导的界面粘附的日益重要。在动态条件下，用几种不同的液体在亚微米的界面间距下直接测量毛细管负压力。待研究的液体包括选定的全氟聚醚（PFPE）油和水。液体性质如分子量、粘度、极性和表面张力的影响将被研究。数学建模将结合实验进行。预计这项工作将导致更好的摩擦接触毛细效应模型，从而为微纳米系统设计者提供改进的数学工具。研究生和本科生将接触到现代实验和计算方法，并将学习液体介质接触的基础知识。此外，佐治亚理工学院将利用现有的美国国家科学基金会资助的项目，为工程和科学领域的代表性不足的学生提供研究生津贴和本科生研究基金，为此项目将做出特别努力，让代表性不足的学生参与其中。

0200681StreatorThis project is a 3-year experimental and theoretical investigation of capillary effects in tribological contacts. The proposed investigation is motivated by the technological trend for smaller and smaller form factors, leading to higher surface-area-to-volume ratios and an increasing significance of liquid-mediated interfacial adhesion. Direct measurements of negative capillary pressures will be conducted with several different liquids at sub-micron interfacial spacings, under dynamic conditions. The liquids to be studied include selected perfluoropolyether (PFPE) oils as well as water. The effects of liquid properties such a molecular weight, viscosity, polarity and surface tension will be investigated. Mathematical modeling will be conducted in conjunction with the experiments. It is anticipated that this work will lead to better models of capillary effects in tribological contacts, thereby providing micro- and nano-system designers with improved mathematical tools. Graduate and undergraduate students will be exposed to modern experimental and computational methods, and will learn fundamentals of liquid-mediated contact. Additionally, special efforts will be made to involve under-represented students in this project by taking advantage of an existing NSF-sponsored program at Georgia Tech that provides graduate stipends and undergraduate research funds to under-represented students in engineering and science.