Yielding of colloidal glassesK. N. Pham1, G. Petekidis2, 3, D. Vlassopoulos2, 3, S. U. Egelhaaf1, P. N. Pusey1 and W. C. K. Poon1
1 SUPA, School of Physics, University of Edinburgh Mayfield Road, Edinburgh EH9 3JZ, UK
2 Institute of Electronic Structure and Laser-FORTH PO Box 1527, Heraklion 71110, Crete, Greece
3 University of Crete, Department of Materials Science and Technology Heraklion, Crete, Greece
received 10 March 2006; accepted in final form 29 June 2006
published online 12 July 2006
We studied yielding in two kinds of colloidal glasses: hard spheres at high concentrations without and with a short-range interparticle attraction induced by adding non-adsorbing polymer. Our oscillatory shear and step strain measurements reveal single and two-step yielding in these two kinds of glasses, respectively. This finding is interpreted in terms of a simple picture: the breaking of local topological constraints (cages) and the breaking of nearest-neighbour bonds.
82.70.Dd - Colloids.
83.50.-v - Deformation and flow.
83.80.Hj - Suspensions, dispersions, pastes, slurries, colloids.
© EDP Sciences 2006