News and Events


2012 年 04 月 11 日
Seminar - Phase field modeling and simulation of nonlinear wrinkling and delamination by Dr. Yong Ni

Date:   11 April 2012 (Wednesday)

Time:   11:00 am – 12:00 pm

Venue:  EF305, The Hong Kong Polytechnic University

The structure of a thin film with internal stress on an elastic substrate has been widely used in thin film technology. The compressed film often leads to buckling instability with formation of wrinkle, buckle-delamination blister or folding pattern. Understanding the film morphology driven by the buckling instability is important in various applications, i.e., flexible microelectronics, graphene nanotechnology, thin film metrology, mechanics-based nanofabrication, and paint. In this talk, the application of a new phase field modeling and simulation to the problem of nonlinear wrinkling and delamination is discussed. The mechanism and conditions for the formation of versatile wrinkling patterns, buckle-delamination are identified, and good agreements with the experimental observations are obtained. The present model provides a powerful tool for the study of the interplay between wrinkling and buckle-delamination in film-substrate systems.

Dr. Yong Ni is a professor of Modern Mechanics at the University of Science and Technology of China (USTC) since 2009,9. He has been selected as the Hundred Talent Program issued by the Chinese Academy of Sciences. He recieved a B.S. degree in Theoretical Applid Mechanics in 2000 and a Ph.D degree in Solid Mechanics in 2004. Prior to joining the USTC, from 2005 to 2009 he worked as a Research Associate at HKU with Prof. A.K.Soh, NIST with Prof. M. Chiang and Rutgers University with Prof. A.G. Khachaturyan. His main research area is microstructure evolution, computational mechanics and materials.