Advanced Characterization of Zirconium Hydrides in Zr-2.5Nb Pressure Tube in CANDU Reactors

In the operation of CANDU reactors, the Zr-2.5Nb pressure tubes holding the cooling water and fuel bundles are susceptible to hydride cracking-induced crack initiation mechanisms, known as delayed hydride cracking and overload crack initiation. For structural integrity evaluation of CANDU pressure tubes, of fracture toughness and hydride crack initiation models were developed. However, the hydride morphology input for the model is still based on microstructures taken decades ago. By applying more advanced electron microscopes and establishing corresponding sample preparation procedures on hydrided pressure tube samples with similar thermo-mechanical history of real in-reactor components, better data input will be generated for the models to ensure more success tube integrity evaluation. Findings from this project will also benefit the industry partner with established sample preparation method for imaging hydrides at different length scales.

Faculty Supervisor:

Zhongwen Yao;Mark Daymond

Student:

Fei Long

Partner:

Kinectrics Inc

Discipline:

Engineering - other

Sector:

Manufacturing

University:

Program: