Atomic-Scale Characterisation of Reactor Pressure Steels

反应堆压力钢的原子尺度表征

• 批准号: 2137687
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2137687
• 关键词: Atomic; Scale; Characterisation; Reactor; Pressure

The reactor pressure vessel (RPV) is a safety critical component of a nuclear fission reactor. Hence, the long-term stability, strength and toughness of RPV steels are of vital importance for the power-generating industry. The main experimental technique to be used will be atom probe tomography. This cutting edge microscopy technique enables a three-dimensional, atom-by-atom characterisation of the microstructure of the steel, providing unique insight into the fundamental mechanisms of solute clustering and the resulting embrittlement. Additional experimental work will involve electron microscopy and mechanical property measurements. This research is critical both for the predicting the safe operating lifetimes of existing fission plants, and also in the design and manufacture of new reactors, such as Small Modular Reactors, in the UK.This is project will enable ongoing collaboration between Oxford and Rolls Royce. The current ageing experiments (approaching 5 years of continuous thermal treatments) will be continued with removal from furnaces and testing/examination of aged samples at suitable intervals. Current mechanistic understanding is that any nano-scale precipitation will be more likely found either on dislocations or grain boundaries. Because of this more emphasis will be placed on grain boundary behaviour and in particular the segregation of elements such as phosphorus, as well as Ni/Mn/Cu. This will require greater use of instruments other than atom probe, such as Focused Ion Beam (FIB) to generate site specific specimen, and Transmission Kikuchi Diffraction (TKD) to characterise the crystallographic misorientation of the grain boundaries.The project also represents an opportunity to continue to collaborate with the Odette Group at UCSB. This collaboration has enabled access to neutron irradiated samples for complementary analysis to our thermally aged counterparts. This has previously led to opportunities to use the facilities at Idaho National Laboratory for the characterisation of active materials. However, it now presents the possibility to exploit the expertise and capabilities at the Culham Centre for Fusion Energy (CCFE) Materials Research Laboratory.The capability for 3D chemically-resolved atomic imaging has exciting implications for unlocking microstructure-property relationships critical to design of new materials, developing processing routes, understanding in-service performance and degradation/failure mechanisms in harsh environments. This research into structural materials for GenIV Small Modular Reactors, will also contribute to safety critical monitoring of reactor steels. As such, this project is directly relevant to multiple EPSRC themes such as Physical Sciences, Manufacturing the Future, Engineering and Energy, across research areas: Nuclear Fission (Maintain), Materials for Energy Applications (Grow), Materials Engineering-Metals and Alloys (Maintain). It falls under the EPSRC themes of a Productive and Resilient Nation, contributing to the renaissance of nuclear research in the UK.

反应堆压力容器（RPV）是核裂变反应堆的安全关键部件。因此，RPV钢的长期稳定性、强度和韧性对于发电行业至关重要。使用的主要实验技术是原子探针断层扫描。这种尖端的显微镜技术能够对钢的微观结构进行三维、逐个原子的表征，为溶质聚集和由此产生的脆化的基本机制提供独特的见解。其他实验工作将涉及电子显微镜和机械性能测量。这项研究对于预测现有裂变工厂的安全运行寿命以及英国小型模块化反应堆等新反应堆的设计和制造都至关重要。该项目将使牛津大学和劳斯莱斯之间的持续合作成为可能。当前的老化实验（接近 5 年的连续热处理）将继续进行，并以适当的时间间隔从熔炉中取出老化样品并进行测试/检查。目前的机理理解是，任何纳米级沉淀更有可能出现在位错或晶界上。因此，我们将更加重视晶界行为，特别是磷以及 Ni/Mn/Cu 等元素的偏析。这将需要更多地使用原子探针以外的仪器，例如聚焦离子束 (FIB) 来生成特定位置的样本，以及透射菊池衍射 (TKD) 来表征晶界的晶体取向错误。该项目还提供了继续与 UCSB 的 Odette 小组合作的机会。此次合作使我们能够获取中子辐照样品，以对我们的热老化样品进行补充分析。这使得我们有机会使用爱达荷国家实验室的设施来表征活性材料。然而，现在它提供了利用卡勒姆聚变能源中心 (CCFE) 材料研究实验室的专业知识和能力的可能性。3D 化学分辨原子成像功能对于解锁对于新材料设计、开发加工路线、了解恶劣环境中的使用性能和退化/失效机制至关重要的微观结构-性能关系具有令人兴奋的影响。这项针对第四代小型模块化反应堆结构材料的研究也将有助于反应堆钢的安全关键监测。因此，该项目与物理科学、制造未来、工程和能源等多个 EPSRC 主题直接相关，研究领域包括：核裂变（维护）、能源应用材料（增长）、材料工程-金属和合金（维护）。它属于 EPSRC 的“富有成效和有弹性的国家”主题，为英国核研究的复兴做出了贡献。