稀土（La、Pr）添加对V-4Cr-4Ti合金的辐照损伤行为的影响机理研究

V-4Cr-4Ti合金因其具有良好的力学性能、热物理性能、低活化性以及与氚增殖剂、冷却剂具有良好的兼容性等，是聚变堆用结构材料的候选材料之一，然而较低的抗拉强度以及辐照硬化等问题，限制了其使用。国内外研究者们通过微量添加合金元素来优化V-4Cr-4Ti合金的机械性能以及耐辐照性能，然而其掺杂元素对钒合金辐照损伤的影响的机制尚不清晰，急需深入研究。本项目拟选取稀土钒合金为对象，研究稀土（La、Pr）添加对钒合金的沉淀相变化规律及其对性能的影响；通过同一系列的自离子辐照，对比性研究不同种类稀土钒合金中辐照缺陷、辐照析出以及辐照硬化行为；通过不同条件自离子辐照，研究稀土钒合金中辐照缺陷、辐照析出以及辐照硬化行为的演变规律，从而揭示稀土添加对V-4Cr-4Ti的辐照损伤行为的影响机制，以期深入理解合金元素影响聚变堆结构材料辐照损伤演化的微观机理，对推动聚变堆关键材料的发展具有重要意义。

V-4Cr-4Ti alloy is one of the candidate structural materials for fusion reactor because of its good mechanical properties, thermophysical properties, low activation and good compatibility with tritium breeder, coolant. However, its application is limited by its low tensile strength, radiation hardening and brittleness. National and international researchers optimize the mechanical properties and radiation resistance of V-4Cr-4Ti alloy by adding a small amount of alloying elements. However, the mechanism of the effect of doping elements on the radiation damage of V-4Cr-4Ti alloy is still unclear, which needs to be further studied. In this project, V-4Cr-4Ti-xRE alloy is selected as the object to study the precipitation phase change rule of RE addition (La, Pr) on vanadium alloy and its influence on properties; the irradiation defects, irradiation precipitation and irradiation hardening behavior of different kinds of V-4Cr-4Ti-xRE alloy are comparatively studied through the same series of self-ion irradiation; the evolution of the irradiation defects, irradiation precipitation and irradiation hardening behavior of the V-4Cr-4Ti-xRE alloy is studied through different conditions of self-ion irradiation, in order to reveal the mechanism of the influence of the RE addition on irradiation damage behavior of V-4Cr-4Ti alloy, to further understand the microscopic mechanism of the influence of alloy elements on the radiation damage evolution of fusion reactor structural materials, and it is of great significance to promote the development of key materials for fusion reactor.