Tan Kah Kee Award in Mathematic and Physical Sciences
Bai Yilong

Mechanician, was born in Xiangyun, Yunnan Province on December 22, 1940. Undergraduate in the department of mechanics, the University of Science and Technology of China, 1958-1963 and postgraduate in the Institute of Mechanics, Chinese Academy of Sciences, 1963-1966. Since 1966, he has been working in the Institute of Mechanics, Chinese Academy of Sciences. He was elected as a member of Chinese Academy of Sciences in 1991 and elected as a member of European Academy of Sciences in 2002. Now he is a professor of the Institute of Mechanics, Chinese Academy of Sciences and serves as the chairman of the academic committee of the state key laboratory of nonlinear mechanics (LNM), General Assembly member of International Union of Theoretical and Applied Mechanics (IUTAM), etc.

He was involved in the projects on the mould strength in metal forming and the synthesis of diamond with explosives as well as the propagation of blast waves. For thermo-plastic shear localization, he established the criteria and laws of its occurrence, evolution and quasi-steady structure (shear band width). Aiming to the mechanism of micro-damage evolution, he created sub-microsecond stress wave technique, established the framework of statistical microdamage mechanics and revealed the ideas, like damage evolution induced catastrophe, etc. He has published one hundred of peer-reviewed papers, two English monographs.

Deformation Localization, Damage, and Catastrophic Failure in Solid Materials


Abstract

Shear deformation localization serves as a precursor to catastrophic failure of materials. Different from the conventional empirical descriptions, the recipient successfully established the governing equations of the thermo-plastic shear deformations. Based on the proposed model, he obtained the criterion to forecast thermo-plastic shear instability and the relevant formulae to predict the characteristic width of shear bands. Aiming to understand the mechanism of material failure induced by micro-damage evolution, the recipient originally developed a theoretical framework of statistical mesomechanics by deriving the evolution equations for the number density of micro-damage and finding their basic solutions. He theoretically revealed and experimentally proved some universal properties in the nonlinear behavior of damages, such as evolution induced catastrophic failure, sample specificity and critical sensitivity, etc. This work provides a new approach to predict catastrophic failure of non-homogeneous brittle materials. Above all, the recipient made "seminal contributions to the theories of shear-band formation and damage in materials".