聚变堆面向等离子体材料须承受极端的辐照环境，特别是氦泡与堆内热应力共同作用，会促使材料力热性能退化。尽管辐照引起的热应力导致氦泡加速生长已被实验揭示，但该条件下氦泡形成的微介观机理尚缺少系统的理论研究。本项目以体心立方微米晶钨为研究对象，基于自主开发的相场模型并结合速率理论，通过对比考察有无热应力及不同大小热应力下氦泡演化动力学行为和形貌特性的差异，阐明热应力环境下钨中氦泡孕育、形成和粗化的微介观机理，并探讨氦泡对热导率变化的贡献。上述研究对于深入理解钨中氦泡形成机理与演化规律有着重要的科学意义，同时也可以为核聚变堆用钨及钨基材料的设计与研发提供理论指导和参考依据。

Numerous helium (He) bubbles are generated in a metal during neutron irradiation, leading to microstructure change and mechanical properties degradation. Although irradiation-induced stress accelerated He bubble growth has been revealed by experiments, there is still absent systemic study on the formation mechanism of He bubble at the mesoscopic spatial scale and long time scale. Here, we propose to investigate the effect of irradiation-induced stress on the growth and coarsening of He bubbles in micron-sized tungsten by developing a model integrating rate theory and phase field method. We aim to clarify the influence of irradiation-induced stress on the incubation, formation and coarsening of He bubbles in a comparative manner. In addition, the effect of He bubbles on the thermal conductivity of tungsten is also studied. This theoretical work will provide useful insights in understanding the irradiation damage mechanism of tungsten and offering guidance for the design and development of pure tungsten and tungsten-based alloys in the fusion reactors.