Welded joints behaviour in high-temperature reactors

焊接接头是反应堆结构中最安全的关键部位之一。经过几十年的运行，它们往往容易损坏，可以被认为是限制英国先进气冷反应堆寿命的因素之一。这是因为焊接过程的复杂性，包括残余应力、变化的微观结构和复杂的几何形状。该项目的目的是通过先进的实验技术，如数字图像相关和同步加速器x射线衍射，确定在焊接接头界面产生的应力集中的临界性。实验工作预计将辅以有限元模拟，以评估焊缝界面累积的蠕变损伤的严重程度。关键的是，关键结果预计将包括在工程师日常使用的完整性评估程序中，以评估反应堆组件的服务适用性。我们的学生为未来的职业发展提供了一个极好的平台，我们的校友在核工业公司担任高层工作。这项工作将与EDF能源公司的专家和固体力学研究小组（SMRG）的其他研究人员合作，在布里斯托尔大学的一个现代化的、设备齐全的高温机械测试设施中进行。SMRG也是英国主要设施的常规用户，如钻石光源和ISIS中子和介子源。

Welded joints are one of most safety critical locations in a reactor structure. They are often prone to damage after decades of operation and can be considered to be one of the life-limiting factors in the UK's advanced gas cooled reactors. This is because of the complexities involved in a weld including the residuals stress, varying microstructure and their complicated geometry. The aim of this project is to identify the criticality of the stress concentration created at the interface of a welded joint through advanced experimental techniques such as Digital Image Correlation and synchrotron X-ray diffraction. The experimental work is expected to be complemented by finite element simulations to assess the severity of the creep damage accumulated at the weld interface. Critically, the key results are expected to be included in the integrity assessment procedures the engineers use day to day to evaluate the fitness for service of reactor components. The studentships offer an excellent platform for future career opportunities our alumni have top level jobs at nuclear industry companies.The work will be carried out in a newly modernised well-equipped high temperature mechanical testing facility at University of Bristol in collaboration with experts at EDF Energy and other researchers in The Solid Mechanics Research Group (SMRG). SMRG is also a regular user of UK major facilities such and Diamond Light Source and ISIS Neutron and Muon Source.