The micromechanics of fracture of hydrides in Zr-2.5Nb CANDU pressure tubes

Zr-2.5Nb CANDU压力管中氢化物断裂的微观力学

基本信息

批准号：
560391-2020
负责人：
Abdolvand, Hamidreza
金额：
$ 3.01万
依托单位：
University of Western Ontario
依托单位国家：
加拿大
项目类别：
Alliance Grants
财政年份：
2021
资助国家：
加拿大
起止时间：
2021-01-01 至 2022-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=721769
关键词：
micromechanics fracture hydrides Zr 2.5Nb

项目摘要

CANDU reactors have been contributing significantly in providing clean energy to Ontario and Canada. More than 50% of electricity in Ontario is generated by CANDU reactors. Most of CANDU reactors are built in 1970s and 1980s and are aging. In order to continue to operate these reactors, engineers are required to demonstrate to regulatory authorities that they are safe. One of the main components that determine the lifetime of CANDU reactors is the zirconium-alloy pressure tubes that contain fuel bundles and separate the hot water coolant from the cold moderator. During operation, hydrogen from hot water diffuses towards the flaws induced in the tube and with time, forms a brittle phase called zirconium hydrides. To ensure the integrity of the tubes and safety of the reactors, it is important to show that a crack will not nucleate in these hydrides. This project focuses on using advanced numerical techniques and diffraction-based experiments to understand how the hydrides that form in the vicinity of flaws will crack and how such cracks lead to failure. Finite element models will be developed and used at Western University, and with the help of graduate students, experiments will be done at Canadian Nuclear Laboratories to study formation of cracks at nano and meso-scales. This will help understand the underlying mechanisms that control fracture of hydrides.The results from this research are expected to help improve the accuracy of the models used in nuclear industry and improve the lifetime of the pressure tubes used in the core of CANDU reactors.

CANDU 反应堆为安大略省和加拿大提供清洁能源做出了重大贡献。安大略省超过 50% 的电力由 CANDU 反应堆产生。大多数 CANDU 反应堆建于 20 世纪 70 年代和 80 年代，并且正在老化。为了继续运行这些反应堆，工程师必须向监管机构证明它们是安全的。决定 CANDU 反应堆寿命的主要部件之一是锆合金压力管，该压力管包含燃料束并将热水冷却剂与冷慢化剂分开。在运行过程中，热水中的氢气会向管内产生的裂纹扩散，随着时间的推移，会形成一种称为氢化锆的脆性相。为了确保管道的完整性和反应堆的安全，重要的是要证明裂纹不会在这些氢化物中成核。该项目的重点是使用先进的数值技术和基于衍射的实验来了解缺陷附近形成的氢化物将如何破裂以及此类裂纹如何导致失效。有限元模型将在西部大学开发和使用，并在研究生的帮助下，在加拿大核实验室进行实验，研究纳米和介观尺度裂纹的形成。这将有助于理解控制氢化物断裂的潜在机制。这项研究的结果预计将有助于提高核工业中使用的模型的准确性，并提高 CANDU 反应堆堆芯中使用的压力管的寿命。