讲座时间：2025年4月15日（星期二）下午16:00
讲座地点：犀浦校区X30280
报 告 人：Prof. Dr. Michael Zaiser
个人简介：
Prof. Michael Zaiser is Chair Professor of Materials Simulation at the Department of Materials Science, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Germany. He is a leading scientist in the modeling and simulation of mechanical behavior and transport properties across a wide range of materials, including crystalline and amorphous solids, nanocomposites, micro- and nanowires, biomaterials, and disordered systems relevant to geological hazards. His work has led to groundbreaking results, including the theoretical prediction of radiation-induced diamond formation from graphite, avalanche-like plasticity behavior in disordered systems, and the design of metamaterials that suppress crack propagation. He has authored over 200 publications, including articles in Science, Nature Communications, Nature Physics, and Nature Reviews Physics. His work has been cited more than 9000 times (Google Scholar), with an h-index of 48, underscoring his significant influence in the field.
讲座内容：
The dynamics of dislocations can be formulated in terms of the evolution of continuous variables representing dislocation densities ('continuum dislocation dynamics'). We show for various variants of this approach that the resulting models can be envisaged in terms of the evolution of order-parameter-like variables that strive to minimize a free energy functional which incorporates interface energy-like terms, i.e. as a phase field theory. We show that dislocation density variables obey non-standard conservation laws. These lead, in conjunction with the externally supplied work, to evolution equations that go beyond the classical framework of Allen-Cahn vs. Cahn–Hilliard equations. The approach is applied to the evolution of dislocation patterns in materials with B1(NaCl) lattice structure and it is demonstrated that it gives access to the formation of cellular dislocation patterns, and the concomitant emergence of both incidental and geometrically necessary dislocation boundaries.
