M.A.Sc. Candidate
Dep. of Mechanical and Materials Engineering, Nicol Hall, 60 Union Street, Kingston, K7L 3N6, Ontario, Canada
Tel: (613) 533-3236
Email:
shuai[dot]wan[at]queensu.ca
Biography
BsC: Shandong University, China
Current research field:
- Zirconium - 2.5wt% Niobium
- Stress relaxation at notch tip
- Finite Element Modeling
Research Interests
Hydrogen ingress is an inevitable phenomenon for Zr-2.5Nb pressure tubes in CANDU. Once the ‘terminal solid solubility’ is exceeded, hydrides will precipitate. Hydride precipitation is particular to tensile stresses within the material and consequently, will align in the stress field of flaw tip. This can result in failure by Delayed Hydride Cracking (DHC). However, as the pressure tube is internally pressurized, it is expected that creep relaxation within the local high stress regions will significantly reduce the local stress at the crack tip. As a result, cracking would be less likely than in a similar flaw where creep did not occur. The aim of the current research is to understand the changes in stress field produced when localized creep occurs in the vicinity of a flaw. Both in situ and ex situ experiments are carried out at the APS at Argonne National Lab. Data was obtained by synchrotron X-ray diffraction in order to make strain maps of the stress field at the notch tip. A finite element model is going to be established to describe the stress field at this location.