In-situ loading during irradiation of materials for fusion applications

聚变反应堆内的材料将经历恶劣的条件，包括高温、负载和辐射。为了成功地设计和建造一个商业上可行的聚变反应堆，我们必须对我们使用的材料在服役期间的性能有很好的了解。不幸的是，目前我们对结构合金在热、载荷和辐射组合条件下的行为的了解在某种程度上是有限的，人们对改变这一点很感兴趣。该项目旨在开发和利用新的先进实验能力，以提高我们对聚变反应堆中合金行为的理解。该项目将结合曼彻斯特道尔顿坎布里安设施(DCF)质子和/或离子辐照期间的原位机械加载和高分辨率辐照后的表征。该项目将在辐照光束线上开发机械钻机能力，并使用世界领先的显微镜、微结构分析和原位高分辨率数字图像相关(HRDIC)作为一种新的变形映射技术，见图1。这将评估辐照对材料力学的影响，为STEP的工程设计提供数据。通过改变辐照条件--剂量、温度和应变率--将有可能展示聚变反应堆内不同的辐照条件如何影响材料性能，从而影响部件寿命。此前，HRDIC技术已被证明在量化未辐照和辐照的低损伤级别的锆合金之间的变形差异方面非常有效[1]。将这种分析技术与现场辐照-机械加载相结合，将对该领域做出重大贡献，并使人们能够更详细地了解辐射诱导效应的机制，有助于改进材料--优化它们以实现核聚变--并验证材料性能模型，以便这些模型可以用作聚变发电厂恶劣环境的预测工具。博士学位将是英国能源署的球形托卡马克能源生产(STEP)计划的一部分，该计划是为了设计和建造一个聚变能源工厂原型而创建的。这一博士项目将有助于评估在核聚变过程中通常经历的恶劣环境下的材料性能，为UKAEA的实验和建模活动提供信息。可能应用于聚变反应堆的候选材料包括马氏体钢、铜铬锆合金和钨合金。这些材料的性能取决于它们的力学性能如何受到聚变堆极端运行条件的影响，特别是辐照过程中蠕变和疲劳的影响。

The conditions materials will experience inside a fusion reactor are severe, combining high temperatures, loads and irradiation. In order to successfully design and construct a commercially-viable fusion reactor, we must have a good understanding of how the materials we use will perform during service. Unfortunately, our understanding of how structural alloys behave in conditions combining heat, load and irradiation is somewhat limited at present, and there in considerable interest in changing this. This project will aim to develop and utilise new advanced experimental capabilities in order to improve our understanding of the behaviours of alloys in fusion reactors.The project will combine in-situ mechanical loading during proton and/or ion irradiation at Manchester's Dalton Cumbrian Facility (DCF) with high resolution characterisation post-irradiation. The project will develop mechanical rig capability on the irradiation beamline and use world-leading facilities for microscopy, microstructural analysis analysis and in-situ High Resolution Digital Image Correlation (HRDIC) as a novel deformation mapping technique, see Fig. 1. This will assess the effect of irradiation on material mechanics, providing data to aid in engineering design for STEP. By varying irradiation conditions - dose, temperature and strain rate - it will be possible to demonstrate how the variable irradiation conditions inside a fusion reactor affect material performance and therefore component lifetime. Previously, the HRDIC technique has proven highly effective in quantifying the differences in deformation between non-irradiated and irradiated zirconium alloys subjected to low damage levels [1]. Combining this analysis technique with in-situ irradiation-mechanical loading will make a significant contribution to the field and enable a more detailed understanding of the mechanisms of irradiation-induced effects, helping to improve materials - optimising them for fusion - and to validate models of material performance so that the models can be used as predictive tools for the harsh environment of a fusion power plant. The PhD will be part of UKAEA's Spherical Tokamak for Energy Production (STEP) programme, which has been created to design and construct a prototype fusion energy plant. This PhD project will help inform the assessment of material performance when subjected to the harsh environments typically experienced during the fusion process, feeding into the experimental and modelling activities at UKAEA. Likely candidate materials for application in fusion reactors include martensitic steels, Cu-Cr-Zr alloys and Tungsten alloys. The performance of these materials depends how their mechanical properties are affected by the extreme operating conditions in a fusion reactor, especially the impact of creep and fatigue during the irradiation process.