美国加州大学伯克利分校Shaofan Li教授学术讲座

Geometrically-Compatible Dislocation Patterns and Multiscale Crystal Plasticity

主讲人 : Shaofan Li

In this talk, we present a major development on atomistic-informed multiscale simulations of plastic deformation in crystalline and amorphous solids.

We shall discuss a recently developed multiscale dislocation pattern dynamics called Multiscale Crystal Defect Dynamics (MCDD), in which we put forth a novel concept of Geometrically-compatible dislocation pattern.  d on this notion and higher order Cauchy-Born rule, we have developed a systematic approach that uses the generic geometrically-compatible dislocation pattern in crystals to establish a multiscale crystal plasticity finite element formulation, or an atomistic-informed crystal plasticity. 

 The main novelties of MCDD- d crystal plasticity are: (1) We have discovered a multiscale quasi-crystal patterns to represent geometrically-necessary dislocation pattern distribution, which is related to the original crystal structure, and (2) We adopt a fourth-order (four scales) Cauchy-Born rule- d strain gradient theory to model constitutive behaviors of various dislocation patterns and crystal defects, and we can simulate single crystal plasticity at sub-micro level or even higher levels. MCDD theory is an atomistic-informed macroscale or multiscale modeling theory that does not require any empirical formalism in the material theory.

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主讲人简介：

Dr. Shaofan Li is currently a full professor of applied and computational mechanics at the University of California-Berkeley. Dr. Li graduated from the Department of Mechanical Engineering at the East China University of Science and Technology (Shanghai, China) with a Bachelor Degree of Science in 1982; he also holds Master Degrees of Science from both the Huazhong University of Science and Technology (Wuhan, China) and the University of Florida (Gainesville, FL, USA) in Applied Mechanics and Aerospace Engineering in 1989 and 1993 respectively. In 1997, Dr. Li received a PhD degree in Mechanical Engineering from the Northwestern University (Evanston, IL, USA), and he was also a post-doctoral researcher at the Northwestern University during 1997-2000.

 In 2000, Dr. Li joined the faculty of the Department of Civil and Environmental Engineering at the University of California-Berkeley. Dr. Shaofan Li is the recipient of IACM (International Association of Computational Mechanics) Fellow Award [2018]; Distinguished Fellow Award of ICCES [2014]; ICACM Computational Mechanics Award [2013], USACM Fellow Award (2013), A. Richard Newton Research Breakthrough Award [2008], and NSF Career Award [2003]. Dr. Li has published more than150 articles in peer-reviewed scientific journals (SCI) with h-index 43 (Google Scholar), and he is also the author of two research monographs/graduate textbooks.