Some Advances for Modeling of Defects in Plasticity Theory

Date: 2021/05/12 - 2021/05/12

Academic Seminar: Some Advances for Modeling of Defects in Plasticity Theory

Speaker: Dr. Yejun Gu, assistant research scientist at Johns Hopkins University

Time: 9:00 a.m.-10:00 a.m., May 12th, 2021

Location: via Feishu

Abstract

A fundamental understanding of the plastic deformation in metallic materials and their failure is essential to improve the performance of materials and accelerate future material development. However, it is difficult to investigate plasticity through only experimental investigations and/or simple analytical models. This talk will present some advances for multiscale modeling of defects in plasticity theory, including dislocation climb models, dislocation-impurity interstitial interaction models, dislocation-substitutional atom interaction models, size effect in plasticity, and some simulation results. In particular, Dr Gu will present recent discrete dislocation dynamics (DDD) simulations results to understand the long-range internal stresses. Dr Gu will also present the derivations and results of the size effect model of materials strength. Finally, the framework to model the interaction between dislocations and impurity interstials will be discussed.

Biography

Yejun Gu is currently an assistant research scientist at Johns Hopkins University (JHU). He received his B.S. in mathematics from Wuhan University in 2012, and earned his PhD in nano science and technology program from the Hong Kong University of Science and Technology in 2016. From 2016 to 2020, he was a postdoctoral fellow at JHU. His research interest is to develop multiscale simulation techniques, and microscale experiments to predict the underlying deformation, damage, and failure mechanisms in materials.