• [2013-04-28]

  Correlating Neutrons Damaged Among Different Irradiation Facilities

Speaker： Prof.  C.H. Woo 

Time：14:30 pm

Date：May 7, 2013

Venue：Room 210, COE Building No.1 

Host: Xiantu He (Academician)

Abstract:

Damage by fast neutrons takes the form of “local explosions” reaching very high temperatures. As the damaged region cools down, lattice defects are “quenched in”, resulting in near-simultaneous creation of a large number of atomic displacements in a small cascade volume. This mode of creation of displacement damage has two characteristics. Firstly, extensive annealing occurs, which only allows a small fraction of the initial displacements to survive as vacancies and interstitials and their clusters, which constitute the primary damage. Through the introduction of production bias, it was already shown in Silkeborg (1989) that the macroscopic manifestation of the damage effects depends almost completely on 3 parameters characterizing the primary damage. To obtain a quantitative description of these parameters naturally becomes the objective of investigation of many recent studies on cascade initiation.  Indeed, to relate the primary irradiation damage to the neutron energy spectra is obviously a crucial first step in correlating irradiation damage among different irradiation facilities for design and regulatory functions.

Biography:

Professor Woo graduated from The University of Hong Kong in Physics and Mathematics, got his PhD in Theoretical Solid-State Physics from University of Waterloo (Canada), and was awarded the D.Sc. degree from HKU in recognition of his contribution in materials science and engineering.   Professor Woo was one of the highest ranking scientists of Atomic Energy of Canada where he has served for 22 years, before returning to join The Hong Kong Polytechnic University in 1996, where he was Chair Professor for 16 years, first in the field of mechanical engineering, and then in the field of solid-state electronics.  He is currently Chair Professor of Nuclear Engineering of City University of Hong Kong. He was one of the pioneers of multiscale multiphysics materials modeling.  His 200+ journal publications cover areas including computational materials science, irradiation damage theory and ferroelectric thin film structures. He is a member of the Hong Kong Academy of Engineering Sciences.