Simultaneous Corrosion/Irradiation Testing in Lead and Lead-Bismuth Eutectic: The Radiation Decelerated Corrosion Hypothesis (RC-3)

铅和铅铋共晶的同步腐蚀/辐照测试：辐射减速腐蚀假说 (RC-3)

• 批准号: EP/T002808/1
• 负责人: Felix Hofmann
• 金额: $ 69.23万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FT002808%2F1
• 关键词: Simultaneous; Corrosion; Irradiation; Testing; Lead

Nuclear fission power plays a vital role in supplying the UK with low carbon footprint electricity. The current UK fleet of nuclear reactors is rapidly ageing, and all of these reactors are scheduled to be removed from service within the next 12 years. Without replacement, the electricity they generate, ~20% of total UK electricity, will need to be provided by other sources, e.g. fossil fuel power stations. This would be detrimental to UK greenhouse gas emissions and contribution to climate change. For successful decarbonisation by the 2050s, UK new build of future fission reactors is urgently needed. Liquid lead (Pb) and lead-bismuth eutectic (LBE) cooled fast reactors promise the best power density and economics among fission reactors. However, for decades now the development of these reactors has been stuck because of concerns about the combined effect of Pb/LBE corrosion and irradiation on the structural materials they would use. Moreover, the problem is that to actually test how bad the corrosion is, one would either have to setup an experiment in an existing research reactor or indeed build a whole new Pb or LBE-cooled research reactor. This would be prohibitively costly, slow and it would be challenging to build and license a test reactor without initial understanding and prediction of material performance. A much faster way of studying combined irradiation and corrosion of materials for Pb/LBE cooled fast reactors is needed!Here we address this problem: Our project partners at MIT, USA, have developed a new, one-of-a-kind facility that allows the simultaneous exposure of materials to Pb/LBE corrosion and insitu irradiation with protons. The protons are used to mimic the effect of neutrons in a fission reactor. Whilst protons don't perfectly mimic the damage caused by neutrons, they capture the key mechanisms well. Most importantly these experiments are much quicker and cheaper than e.g. in-reactor material testing. Using this new tool, we will explore the performance of five of the current front-runner alloys for cladding and structural components in Pb/LBE fast reactors. We will also compare the results against more traditional Pb/LBE corrosion tests to make sure the new combined irradiation and corrosion facility performs as anticipated. After exposure, the Oxford partners of the project team will then analyse the samples to determine how Pb/LBE corrosion proceeds in the presence of irradiation, and how this differs from Pb/LBE corrosion without irradiation. Curiously our initial results show that irradiation slows down the rate of corrosion! To explore and understand this behaviour, we will perform characterisation of the structure and chemical composition of samples after exposure, from the macroscopic down to the atomic scale. This microstructural characterisation will be combined with mechanical testing of the exposed materials carried out by US project partners at the North Carolina State University. Overall the results from this project will finally address how simultaneous irradiation modifies the corrosion behaviour of alloys for Pb/LBE cooled fast reactors. It will allow us to identify which of the tested candidate alloys performs best and what the key mechanisms are that control its degradation during combined corrosion and irradiation. This information is vital for overcoming the current stagnation of progress in the development of Pb/LBE cooled fast reactors, and to allow directed optimisation of the structural and cladding materials they require.

核裂变功率在为英国提供低碳足迹的电力方面起着至关重要的作用。当前的英国核反应堆机队正在迅速衰老，所有这些反应堆计划在未来12年内将其从服务中删除。如果没有更换，它们产生的电力占英国总电力的约20％，需要由其他来源提供，例如化石燃料电站。这将不利于英国温室气体排放和对气候变化的贡献。为了在2050年代取得成功的脱碳化，迫切需要英国的未来裂变反应堆的新建。液体铅（PB）和铅孔恒星（LBE）冷却的快速反应器承诺在裂变反应堆中具有最佳的功率密度和经济性。但是，几十年来，这些反应器的发展一直被卡住，因为人们担心PB/LBE腐蚀和辐照对它们使用的结构材料的综合作用。此外，问题在于，要实际测试腐蚀有多严重的情况，人们要么必须在现有的研究反应器中设置实验，要么确实构建了全新的PB或LBE冷却的研究反应器。这将是高昂的代价高昂，缓慢的，并且在没有初始理解和预测材料性能的情况下建造和许可测试反应堆将是一项挑战。需要更快地研究PB/LBE冷却快速反应器材料的组合辐射和腐蚀的方法！在这里我们解决了这个问题：我们在美国麻省理工学院的项目合作伙伴开发了一种新的，一种独特的设施，允许同时暴露于PB/LBE腐蚀和与蛋白酶的材料中的PB/LBE腐蚀和插入。质子用于模仿裂变反应器中中子的作用。尽管质子并不能完全模仿中子造成的损害，但它们可以很好地捕获关键机制。最重要的是，这些实验比例如反应器材料测试。使用此新工具，我们将探索PB/LBE快速反应器中五个用于覆层和结构组件的前跑合金的性能。我们还将将结果与更传统的PB/LBE腐蚀测试进行比较，以确保新的组合辐射和腐蚀设施能够按预期执行。暴露后，项目团队的牛津合作伙伴将分析样品，以确定在存在照射的情况下PB/LBE腐蚀如何进行，以及这与PB/LBE腐蚀无辐照的差异。奇怪的是，我们的最初结果表明，辐射降低了腐蚀的速度！为了探索和理解这种行为，我们将对暴露后样品的结构和化学组成进行表征，从宏观到原子量表。这种微观结构表征将与美国项目合作伙伴在北卡罗来纳州立大学进行的暴露材料进行机械测试。总体而言，该项目的结果最终将解决同时辐射如何改变PB/LBE冷却快速反应器合金的腐蚀行为。它将使我们能够确定哪些经过测试的候选合金表现最佳，哪些关键机制是控制其在腐蚀和辐照过程中降解的关键机制。该信息对于克服PB/LBE冷却快速反应堆的开发过程中目前的停滞，并允许对其所需的结构和覆层材料进行定向优化。

项目成果

Characterisation of corrosion damage in T91/F91 steel exposed to static liquid lead-bismuth eutectic at 700-715 °C

T91/F91钢在700-715℃静态液态铅铋共晶中的腐蚀损伤表征

• DOI: 10.1016/j.jnucmat.2023.154687
• 发表时间: 2023
• 期刊: Journal of Nuclear Materials
• 影响因子: 3.1
• 作者: Lapington M

Characterisation of Corrosion Damage in T91/F91 steel exposed to Liquid Lead-Bismuth Eutectic

T91/F91 钢在液态铅铋共晶中的腐蚀损伤表征

• DOI: 10.48550/arxiv.2302.03470
• 发表时间: 2023
• 作者: Lapington M