Exploration of Potential Material - Coolant System in Application to A First Wall Structure of Fusion Reactors

需要开发融合反应器的第一堵墙结构，分离等离子体和能量转换系统，与材料有关的问题的解决方案，例如辐射诱导的退化和与环境的兼容性。在这个项目中，一个新的设计概念被提议为这个问题提供一个潜在的解决方案，在哪里，压力过高的蒸汽被用作冷却剂。一项实验评估是通过使用加压超热蒸汽（高达70 ° C， 100巴）作为测试环境的多种候选聚变结构材料的兼容性。经测试的候选材料包括（1）低激活铁锰钢F82 H， （2）钒合金，和（3）基于TiAl的金属复合物。根据氧化物量表分析的氧化物比率和结果，随后的综合物已被绘制;1.基于TiAl的合金在过热蒸汽环境中展示了最高的氧化抵抗力。F82 H的蒸汽氧化特性是等效的，具有较高的性能。 ... More USC锅炉应用的耐热钢。基于TiAl的合金和F82 H都具有与超热蒸汽环境相适应的氧化率点的视图。在特殊的，Ti-Al-V合金中，在房间温度下有8%的导电性，在过热蒸汽中显示出优异的氧化抵抗力。Al-D22-D2O-D23-D2 did not form as a continuous layer both for TiAl and Ti-Al-V in superheated steam， where oxidation potential of the environment was not high， and hence，Al-D22-D2O-D23-D2 did not work as a diffusion barrier。However， the relatively low oxidation potential of the environment does not allow to form V-D22-D2O-D25-D2。因此，加速氧化并没有对Ti-Al-V进行充分的氧化抵抗力。Ti-Al-V的优异氧化抵抗力被解释为，在氧化物尺度TiO-D22-D2中氧化物尺度中的氧化物真空浓度较低，与较小的原子辐射与Ti相比，作为一个结果，氧化物分解的扩散率。Less（低）

To develop a first wall structure of fusion reactors, which separates plasma and energy conversion system, solutions for material-related issues, such as irradiation induced degradation and compatibility with environments, are required. In this project, a new design concept was proposed to give a potential solution for this problem, where pressurized superheated steam is used as coolant. An experimental evaluation was carried out of the compatibility of several candidate fusion structural materials using pressurized superheated steam (up to 70℃, 100 bar) as test environment. The tested candidate materials include (1) low-activation ferritic-martensitic steel F82H, (2) vanadium alloys, and (3) TiAl-based intermetallic compounds. Based on the oxidation rates and results of oxide scale analysis, following conclusions were drawn;1. TiAl-based alloys showed the highest oxidation resistance in superheated steam environment. Steam oxidation property of F82H was equivalent to that of advanced … More heat-resistant steels for USC boiler application. Both the TiAl-based alloys and F82H have sufficient compatibility with superheated steam environment from an oxidation rate point of view.2. In particular, Ti-Al-V alloy, which has about 8% ductility at room temperature, showed excellent oxidation resistance in superheated steam.3. AlィイD22ィエD2OィイD23ィエD2 did not form as a continuous layer both for TiAl and Ti-Al-V in superheated steam, where oxidation potential of the environment was not high, and hence, AlィイD22ィエD2OィイD23ィエD2 did not work as a diffusion barrier. However, the relatively low oxidation potential of the environment does not allow to form VィイD22ィエD2OィイD25ィエD2. Therefore, accelerated oxidation did not occur for Ti-Al-V. The excellent oxidation resistance of Ti-Al-V was explained that substitutional solid solution of V in the oxide scale TiOィイD22ィエD2 lowered concentration of oxygen vacancy in the oxide scale due to smaller atomic radius of V compared with Ti and, as a result, diffusion rate of oxygen decreased. Less