Contribution of colloidal forces in non-contact area to the adhesion between a micro-probe and a substrate surface: Theoretical analysis
Document Type
Article
Publication Date
1-1-2009
Abstract
Colloidal forces outside the microscopic probe (particle)-substrate adhesion contact area were analyzed theoretically. Equations describing the van der Waals, electrical double layer, and hydrophobic forces were derived for the non-contact area of a probe-substrate system assuming a simple sphere-flat geometry. Two cases were considered: particles freely resting on the substrate surface and particles pulling off the substrate. The results of modeling presented in this communication suggest that the adhesion of fine particles (microscopic and sub-microscopic particles) to flat surfaces can be affected by the forces acting outside the contact area. However, due to increased distance between the particle and substrate during separation, both the van der Waals and electrostatic forces acting outside the contact area are negligibly small compared to the short-range adhesion forces and they do not contribute to the measured pull-off force to any great extent for most systems. On the contrary, our calculations suggest that the long-range hydrophobic forces can contribute to the strength of adhesion between hydrophobic fine particles and hydrophobic substrates. © 2009 VSP.
Publication Title
Journal of Adhesion Science and Technology
Recommended Citation
Drelich, J.,
Long, J.,
Masliyah, J.,
&
Xu, Z.
(2009).
Contribution of colloidal forces in non-contact area to the adhesion between a micro-probe and a substrate surface: Theoretical analysis.
Journal of Adhesion Science and Technology,
23(1), 125-138.
http://doi.org/10.1163/156856108X344081
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/12728