Abstract

In this lecture, the speaker will present the theoretical and computational formulation of a Multiscale Crystal Defect Dynamics (MCDD) that is basically an atomistically-informed dislocation pattern dynamics. The main novelties of the proposed MCDD are that: (1) He uses the dual-lattice tessellation to construct a pre-defect process zone model that can represent different types of crystal defects in a single crystal; (2) He adopts a fourth-order (four scales) Cauchy-Born-rule based strain gradient theory to model constitutive behaviors of various defect process zones, and that (3) He employs the Barycentric finite element technique to construct finite element shape functions for polygonal and polyhedral process zone elements. The proposed MCDD method provides an efficient and viable alternative for both molecular dynamics (MD) and dislocation dynamics (DD) in simulations of dislocation pattern evolutions, and crystal plasticity. In particular, MCDD offers a mesoscale description for dynamic lattice microstructure, defect microstructure, and their interactions. The method offers a possible solution for studying nanoscale and mesoscale crystalline plasticity.

About the speaker

Prof Shaofan Li received his PhD in Mechanical Engineering from Northwestern University in 1997. He joined the University of California, Berkeley in 2000 and is currently a Professor at the Department of Civil and Environmental Engineering.

Prof Li’s research focuses on atomistic and multiscale simulations, bio-mechanics and bio-physics, computational mechanics, micromechanics and nanomechanics of materials, soft matter mechanics and physics.

Prof Li received numerous awards including the IACM (International Association for Computational Mechanics) Fellows Award (2018), and the US National Science Foundation CAREER Award (2003). He was also elected a fellow of the United States Association for Computational Mechanics in 2013.
 

For attendees’ attention

The lecture is free and open to all. Seating is on a first come, first served basis.

HKUST Jockey Club Institute for Advanced Study
Enquiries: ias@ust.hk / 2358 5912
http://ias.ust.hk