2006/07/29 by Sujata Tarafdar, Dibyendu Mal, Tarafdar, Sujata +6
Engineering · Materials Science · Physics and Astronomy · #Granular flow and fluidized beds #Material Dynamics and Properties #Soil and Unsaturated Flow #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.cond-mat/0607787
5pages, 3 figures
arxiv created 2006/07/29 · arxiv updated 2009/12/01
Crack patterns in a layer of laponite gel allowed to dry in a static electric field are studied. Crack patterns in natural and synthetic clays have been studied extensively with interesting results. This is the first report of such an observation in a radial electric field. The nano-sized disc-like laponite particles carry a quadrupole moment due to their charge distribution. The interaction of the quadrupole moment with the field gradient in a non-uniform field of radial symmetry is probably responsible for the characteristic pattern observed. The cracks start radially from the positive electrode. The same geometry with no field does not produce the characteristic pattern, neither does a uniform field with rectangular geometry.