弥散强化钨的相界特性对其氦辐照损伤及滞留行为的影响研究

Dispersion strengthened tungsten has been regarded as one of the most promising plasma-facing materials for future fusion reactors, due to its good low-temperature ductility, high recrystallization temperature, and excellent irradiation resistance. Different kinds of dispersions and variants of the preparation processes of tungsten alloys give rise to the obviously different microstructures of the phase boundaries in dispersion strengthened tungsten. So far, relevant research about the effect of dispersion on H/He irradiation-induced damage and H/He retention is very limited. This project starts from the intrinsic characteristic of dispersion strengthened tungsten and aims to investigate the effect of phase boundary character on He irradiation-induced damage around phase boundary of dispersion strengthened tungsten, according to the in-situ He ion irradiation experiments of samples with typical coherent and incoherent phase boundaries. For example, the average size, morphology, and distribution of He bubble around the phase boundary will be investigated. Moreover, the effect of dispersion on the the initiation, growth, and distribution of the nanostructure on the surface of dispersion strengthened tungsten will be investigated carefully, according to the low energy, high flux helium plasma irradiation experiments. Additionally, the influence of dispersion on He retention and desorption behavior, e.g. the shift of He desorption peak, in the irradiated sample will be investigated by high vacuum thermal desorption spectrography. The corresponding underlying mechanisms will also be investigated deeply. This project will supply experimental support and theoretical guidance for the design, preparation, and application of advanced tungsten-based plasma facing materials for fusion reactors.

弥散强化钨具有低温韧性好、再结晶温度高和抗辐照损伤能力强等特性，被认为是未来核聚变堆中最有前途的面向等离子体材料之一。弥散强化钨中的相界微结构会因弥散相种类及钨合金制备工艺的不同而具有明显的差异。目前，关于相界对氢氦辐照损伤行为和氢氦滞留行为影响规律的研究还十分有限。本项目将从弥散强化钨的本征特性出发，基于具有典型共格相界和典型非共格相界的弥散强化钨合金样品，通过其原位氦离子辐照实验和低能大束流氦等离子体辐照实验，研究弥散强化钨的相界特性对相界处辐照损伤（如氦泡大小、形貌及分布等）行为及弥散强化相对表面辐照损伤（如纳米结构形成、生长及分布等）行为的影响规律及其物理机制。同时，通过高真空热脱附实验，研究弥散强化相对氦滞留及脱附（如脱附峰的变化）行为的影响规律及其微观机理。本项目的研究将为核聚变堆用先进钨基面向等离子体材料的设计、制备及应用提供实验支撑和理论指导。

弥散强化钨具有低温韧性好、再结晶温度高和抗辐照损伤能力强等特性，被认为是未来核聚变堆中最有前途的面向等离子体材料之一。弥散强化钨中的相界微结构会因弥散相种类及钨合金制备工艺的不同而具有明显的差异。目前，关于相界对氢/氦辐照损伤行为和氢/氦滞留行为影响规律的研究还十分有限。本项目从弥散强化钨的本征特性出发，基于具有典型共格相界的氧化钇弥散强化钨和典型非共格相界碳化锆弥散强化钨合金样品，通过原位氦离子辐照实验和低能大束流氢等离子体辐照实验，研究了弥散强化钨的相界特性对相界处辐照损伤行为（如氦泡大小、形貌及分布等）行为及弥散强化相对表面辐照损伤（如纳米结构形成、生长及分布等）行为的影响规律及其物理机制的影响规律。提出了通过微观界面设计以提高其抗辐照性能的可行性方案，该方案对具有优异热力学性能和抗辐照性能的先进钨基面向等离子体材料的研发具有重要的学术价值和应用价值。