As the use of soft and compliant materials is rapidly penetrating modern engineering practice, materials are expected to perform at large strains and deep into the nonlinear regime. Although pushing materials to their extremes often exposes unique phenomena and instabilities that were traditionally avoided in engineering, an emerging field of mechanics aims to harness and exploit these rapid morphological changes for design of novel devices. Remarkably, nature has also been shown to exploit instability; a bi-stable mechanism is thought to absorb shocks in our muscles, and growth-induced instability is thought to promote rapid changes of shape and even cell movement. A ubiquitous growth mechanism, in both natural and engineered systems, is surface growth, in which material associates or dissociates on the boundaries of a body. It is the fundamental mechanism by which biological materials grow and is increasingly applied in engineering processes for fabrication and self-assembly. In this talk I will overview some recent work which explores the nonlinear mechanics of growth and instability in soft and biological materials. We will discuss multiple instability modes that appear in finite elastic layers subjected to tensile loads, and upon peeling, then we will shift to discuss recent progress in modeling surface growth processes with coupled diffusion.
About the Speaker
Tal Cohen joined the Department of Civil and Environmental Engineering at MIT as Assistant Professor in 2016 and received a joint appointment in the Department of Mechanical Engineering in 2017. She received both her MSc and PhD at the Faculty of Aerospace Engineering at the Technion in Israel, under the supervision of Prof. David Durban. Following her graduate studies, Tal was a postdoctoral fellow for two years (2014-2015) at the Department of Mechanical Engineering at MIT under the mentorship of Prof. Rohan Abeyaratne, and continued for an additional postdoctoral period at the School of Engineering and Applied Sciences at Harvard University, under the joint mentoring of Professors Katia Bertoldi and L. Mahadevan (2016). Her research is broadly aimed at understanding the nonlinear mechanical behavior and constitutive sensitivity of solids. This includes behavior under extreme loading conditions, involving propagation of shock waves and dynamic cavitation, material instabilities, and material growth.
Host: Professor Shelby Hutchens
* Times, dates, and titles are subject to change. Check mechanical.illinois.edu for updated information. This seminar counts toward the requirements for ME 590 and TAM 500.