This is a webinar event.
Speaker: Sid Pathak, Assistant Professor of Materials Science and Engineering at Iowa State University
Title: Collective Behavior of Vertically Aligned Carbon Nanotubes (VACNTs): from a Single Tube towards Complex Networks
Abstract: In this seminar we discuss the mechanical behavior of vertically aligned carbon nanotubes (VACNTs) also known as carbon nanotube (CNT) arrays, bundles, brushes, foams, forests, mats, and turfs. VACNTs are complex, hierarchical structures of intertwined tubes arrayed in a nominally vertical alignment due to their perpendicular growth from a stiff substrate. They are a unique class of materials having many of the desirable thermal, electrical, and mechanical properties of individual carbon nanotubes, while exhibiting these properties through the collective interaction of thousands of tubes on a macroscopic scale.
We will explore the synthesis techniques by which VACNTs are synthesized, which is the primary factor affecting their complex, hierarchical morphology. This microstructure, in turn, affects their mechanical behavior, in particular the modulus, buckling strength, and recoverability. Using nanomechanical testing techniques, we compare the mechanical response of VACNTs under different loading conditions, namely compression and indentation. We analyze the resultant large variation in structure and properties of VACNTs (porosity, CNT tube thickness, modulus, buckling strength), their large scale deformation and buckling behavior, viscoelasticity and potential applications.
Bio: Dr. Sid Pathak is an assistant professor in the Materials Science and Engineering department at Iowa State University. Prior to starting his faculty career, he was a Director’s Postdoctoral Fellow 2012-2015 at Los Alamos National Laboratory (LANL), and a Keck Institute Postdoctoral Fellow at Caltech (2010-2012). His research interests are in the (i) mechanistic design of multi-layered composites, for both biological, structural and functional applications, and (ii) quantitative understanding of their local mechanical structural changes under extremes of temperature, strain rate and damage (irradiation). He has co-authored >60 peer reviewed articles and 2 book chapters in various scientific journals. He has received numerous scientific awards based on his work including the 2017 TMS Young Leaders Professional Development Award, one of the 2019 Top UNR Researchers for his university, as well as the 2019 DARPA Young Faculty Award and the 2020 NSF EPSCoR Research Fellowship.
Seminar Host: Xiaoli Tan
Zoom Link: https://iastate.zoom.us/j/95915889283