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Frictional forces between cohesive powder particles studied by AFM.

Robert Jones·Hubert M Pollock·Derek Geldart·Ann Verlinden-Luts
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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.

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FrictionMicroscopy, Atomic ForcePowdersSurface PropertiesJournal ArticleResearch Support, Non-U.S. Gov't

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Robert Jones, Hubert M Pollock, Derek Geldart, Ann Verlinden-Luts. 2004. Frictional forces between cohesive powder particles studied by AFM.. https://doi.org/10.1016/j.ultramic.2004.01.009

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