COLÓQUIO- IFUSP:Stress Enhancement in the Delayed Yielding of Colloidal Gels
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Publicado em Mon Oct 15 10:01:38 GMT-03:00 2012
Formatos:
MP4
(640 X 360 px)
Evento:
IFUSP - Colóquio - 2012
Networks of aggregated colloidal particles are solidlike and can sustain an applied shear stress while exhibiting little or no creep; however, ultimately they will catastrophically fail. We show that the time delay for this yielding decreases in two distinct exponential regimes with applied stress. This behavior is universal and found for a variety of colloidal gel systems. We present a bond-rupture model that quantitatively describes this behavior and highlights the role of mesoscopic structures. Our result gives new insight into the nature of yielding in these soft solid materials.