Topic: Failure and Strength of Composite Materials

Speaker: Prof. Huang Zhengming, Tongji University

Time：Friday, April 9, 10:00 am

Venue: C708, New Main Building

Abstract:

The failure of the composites originates from the matrix except that the axial failure may originate from the fibers. The reason why the strength analysis of composite materials is difficult is that the prediction of matrix failure is not accurate. The fundamental reason is that the existing theory can only calculate the mean stress of the matrix, yet the failure analysis of composite materials must be based on the true stress. After the true matrix stress is obtained, many challenging problems can be solved, e.g., when does the fiber-matrix interface crack under any given load? Why does the shear deformation of brittle composites even exceed the elastoplastic deformation of pure matrix? Why does the compressive strength of composites along the fiber direction almost remain unchanged while the strength of carbon fibers from T300 to T1100 increases greatly? This report introduces how to calculate the true stress of the matrix and how to solve these problems.

Biography of the Speaker:

Dr. Huang Zhengming is a professor at the School of Aerospace Engineering and Applied Mechanics, Tongji University. He proposed the unified elastic-plastic constitutive theory and the bridging model for composites. More than 220 research papers based on the bridging model have been published by other researchers at home and abroad. He has published 4 books, 8 co-authored chapters, 210 journal articles and received 12 patents for invention. One of his papers has received more than 5,700 citations in Web of Science.

School of Aeronautic Science and Engineering