Seminar - Size-dependent Probabilistic Damage Micromechanics and Toughening Mechanism for Particle/Fiber Reinforced Composites by Professor J. Woody Ju
日期：2019 年 05 月 28 日 ( 星期二)
Time：11:00 am - 12:00 pm
A micromechanical framework is proposed to predict the deformation responses of particle-reinforced metal matrix composites by invoking essential features of dislocation plasticity. First, within the framework of probabilistic micromechanical formulation, the damage induced by the manufacturing process and by the external mechanical loading in the presence of thermal residual stress is considered. Subsequently, the effective elastic moduli of four-phase composites, consisting of a ductile matrix and randomly located spherical intact or damaged particles are derived. Further, the size-dependent plastic deformation behaviors of particle-reinforced metal matrix composites are predicted with a micromechanics-based dislocation theory. The density of dislocations due to the thermal contraction mismatch and the plastic deformation mismatch are taken into consideration. Based on a frictional shear-slip relationship, the effect of fiber-bridging mechanism is reflected by the toughening mechanism of unidirectional fibrous composites.
Professor Jiann-Wen Woody JU received his M.S. and Ph.D. degrees from the UC Berkeley. He is a senior Professor at UCLA, and served as the Department Chair of Civil and Environmental Engineering. Prof. Ju served as an Associate Editor for the ASME Journal of Engineering Materials & Technology, and for the ASME Journal of Applied Mechanics from 1995 to 2002. He is currently the Editor-in-Chief of the International Journal of Damage Mechanics, an Associate Editor of the ASCE J. of Nanomechanics and Micromechanics, and an Editorial Board member of the Acta Mechanica. He served as the ACI 446 Committee Chair. Prof. Ju received the 1991 Presidential Young Investigator Award from NSF and White House, 1991 Alfred Rheinstein Faculty Award from Princeton Univ., 1997 ASCE Walter Huber Civil Engineering Research Award, 1998 ASME Fellow Award, 2000 ACI-James-Instruments Award in NDE, 2006 ASCE Fellow Award, 2007 USACM Fellow Award, 2008 ACI Fellow Award, 2008-2009 Invited Chair Professor from University of Paris VI and ENS Cachan (France), 2008 Publication Award of Merit from the Structural Engineers Association, 2009-2012 Chang-Jiang Scholar Chair Professor (Ministry of Education, China), 2010 IACM Fellow Award, 2010 Kwang-Hua Chair Professor (Tongji University), 2011-2013 Tongji Univ. Chair Professor, National 1000 Talents Program (Short-Term) Distinguished Chair Professor (2013-present), Tongji University Distinguished Chair Professor (2013-present), Guangxi University Distinguished Chair Professor (2013-present), 2013 ICACM Award, and Honorary Distinguished University Professor from Southwest Jiaotong University (2015-present), 2018 ICDM-3 Lifetime Achievement Medal, and 2018 EU Academy of Sciences Member, etc. Prof. Ju has published more than 140 SCI-indexed scholarly journal papers. Furthermore, Prof. Ju’s journal publications have been highly cited by the Web of Science (SCI); his h-index is currently 41 (Google Scholar). His research interests and research projects encompass structural engineering, structural mechanics, computational mechanics, computational damage, healing and fracture mechanics, micromechanics and nanomechanics of composites, multiscale material modeling, finite elements, biomechanics, computational geomechanics and geotechnical engineering, reliability, service life predictions, durability of concrete and cementitious composites, sulfate attack problems, environmental assessment and hazard, risk analysis and management, hazard mitigation, multiphase porous flow and transport, and wind-wave-bridge interactions and damage effects, etc.