Small Grant for Exploratory Research (SGER) on Development of Nanoparticle Visualization Techniques for Tribological Applications

9977314 yodaa在SGER奖下，将开发实验技术，用于可视化纳米级颗粒与固体表面在软弹性流体动力摩擦学体系中的力学和化学相互作用。该方法使用荧光指示剂染色的颗粒直接可视化颗粒力学和化学。这种技术的一种变体，“粒子接近传感”，将只看到0.1-1毫米范围内的粒子表面-即。即与表面相互作用的粒子。这些技术将用于研究三体相互作用一旦适当的方法“标记”亚微米指示粒子已经开发出来。可视化将用于研究悬浮在光滑刚性表面和粗糙弹性表面之间界面的流体中的颗粒如何被输送到界面并与两个表面相互作用。该研究将有助于解决诸如表面粘附力和布朗运动如何影响三体相互作用，第三体相互作用的时间尺度是什么，以及磨料颗粒实际与两个表面相互作用的比例等问题。在这项研究中开发的技术和实验将有助于对三体相互作用的基本理解。这种理解将影响广泛的应用，从流体膜中的固体污染物到润滑剂和表面处理中使用的颗粒添加剂。磨损固体表面的颗粒动力学的物理基础模型对于理解密封件和轴承的退化以及优化抛光等工艺具有特别重要的意义

9977314YodaUnder an SGER award experimental techniques will be developed for visualizing the mechanical and chemical interactions of nano-scale particles with solid surfaces in the soft elastohydrodynamic tribological regime. The approach uses particles dyed with fluorescent indicators to directly visualize particle mechanics and chemistry. A variant of this technique, "particle proximity sensing," will visualize only particles which are within 0.1-1 mm of the surface-i.e., the particles which actually interact with the surface. These techniques will be used to study three-body interactions once appropriate methods for "marking" sub-micron indicator particles have been developed. The visualizations will be used to investigate how particles suspended in a fluid at the interface between a smooth, rigid surface and a rough, elastomeric surface are transported into the interface and interact with both surfaces. The study will help resolve issues such as how surface adhesion forces and Brownian motion affect three-body interaction, what the time scales of third body interaction are, and what fraction of the abrasive particles actually interact with both surfaces.The techniques and experiments developed during this research will contribute to a fundamental understanding of three-body interactions. This understanding will impact a wide range of applications ranging from solid contaminants in fluid films to particle additives used in lubricants and surface treatments. Physically based models of the dynamics of the particles which wear solid surfaces will be of particular importance for understanding degradation of seals and bearings and for optimizing processes such as polishing.***