通过原子力显微镜研究粘性粉末颗粒间的摩擦力。

Frictional forces between cohesive powder particles studied by AFM.

作者信息

Jones Robert, Pollock Hubert M, Geldart Derek, Verlinden-Luts Ann

机构信息

Department of Physics, University of Lancaster, Lancaster LA1 4YB, UK.

出版信息

Ultramicroscopy. 2004 Jul;100(1-2):59-78. doi: 10.1016/j.ultramic.2004.01.009.

DOI:10.1016/j.ultramic.2004.01.009

PMID:15219692

Abstract

A range of commercially important powders (hydrated alumina, limestone, titania and zeolite) and glass ballotini were attached to atomic force microscope cantilevers, and inter-particle friction forces studied in air using lateral force microscopy (LFM). The in situ calibration procedure for friction forces is described. LF images, line profiles, LF histograms, surface roughness, pull-off forces, and the load dependence of friction in the range 0-25 nN were studied for both particle-particle and particle-wall (steel) contacts. The single-particle friction results are discussed in terms of contact mechanics theory. Particle-particle contacts showed load-dependent friction, involving single asperity contacts (non-linear behaviour) or multi-asperity contacts (linear behaviour). Particle-wall contacts usually showed little load dependence and were more adhesive. The results are also related to shear stress-normal stress data (yield loci) for the same materials from bulk shear testers.

摘要

一系列具有商业重要性的粉末（水合氧化铝、石灰石、二氧化钛和沸石）以及玻璃微珠被附着在原子力显微镜悬臂上，并使用侧向力显微镜（LFM）在空气中研究颗粒间摩擦力。描述了摩擦力的原位校准程序。研究了颗粒 - 颗粒和颗粒 - 壁（钢）接触在0 - 25 nN范围内的侧向力（LF）图像、线轮廓、LF直方图、表面粗糙度、拉脱力以及摩擦力与载荷的关系。根据接触力学理论讨论了单颗粒摩擦结果。颗粒 - 颗粒接触显示出与载荷相关的摩擦力，涉及单粗糙峰接触（非线性行为）或多粗糙峰接触（线性行为）。颗粒 - 壁接触通常显示出较小的载荷依赖性且粘性更强。这些结果还与来自体剪切测试仪的相同材料的剪应力 - 正应力数据（屈服轨迹）相关。