Levich Institute Seminar Announcement, 01/29/2008
Steinman Hall, Room #312
(Chemical Engineering Conference Room)
Professor Jacob Israelachvili
University of California, Santa Barbara
Department of Chemical Engineering
"The Transition from Liquid to Solid 'Failure' Mechanisms"
[This is a CCNY/Columbia NSF-IGERT Soft Materials seminar]
When a liquid column snaps or two droplets separate, they do this in a way that is fairly well understood in terms of their surface tension and viscosity. When brittle solids fail, by a rapid cracking and fracturing, the mechanisms are quite different and appear to depend on different ‘material’ properties. We have studied how time, rate, temperature and viscosity affect the ‘transition’ from liquid-like to solid-like failure. I will describe and visually demonstrate our results, which suggest that the transition may be a continuous one, i.e., one can go continuously from one to the other by simply changing the experimental conditions; but the transient deformations of the materials during the changing failure processes are very complex.
BRIEF ACADEMIC/EMPLOYMENT BACKGROUND:
CURRENT RESEARCH INTERESTS:
Israelachvili's research interests are in the general area of intermolecular and intersurface forces in biological, complex fluid and materials systems.