Single-phase multi-principal element alloys can have low activation and rapid induced radioactive decay properties that make them ideal structural materials for the first wall/cladding structure of nuclear fusion reactors. The present work proposes the design of multi-principal element alloys consisting of low activation elements Fe, Ti, Cr, V, and W with both equiatomic and optimized compositions. The optimal composition of the multiple components is based on the formation of a single-phase solid solution with a minimal Gibbs free energy. The microstructures and mechanical properties of the alloys are investigated. The equiatomic alloy is observed to be composed of dendritic crystals consisting of a body-centered cubic (bcc) solid solution phase and a complex intermetallic compound, while the optimized alloy is composed of cellular dendritic crystals consisting of a single bcc solid solution phase in its as-cast state. Homogenization treatment is observed to reduce the fracture strength of the equiatomic alloy due to grain coarsening, although it has little effect on the hardness and other mechanical properties. However, homogenization increased the hardness and compressive yield strength of the optimized alloy to different degrees. The optimized alloy has better plastic toughness than the equiatomic alloy, which increases its workability and radiation resistance.

单相多原则元素合金可以具有低活化和快速诱发的放射性衰变特性，使其成为核聚变反应堆第一壁/覆层结构的理想结构材料。本工作提出了一种由低活化元素Fe，Ti，Cr，V和W组成的多主要元素合金的设计，该元素既具有等原子又具有优化的组成。多种组分的最佳组成基于具有最小吉布斯自由能的单相固溶体的形成。研究了合金的微观结构和力学性能。观察到该等原子合金由树枝状晶体组成，该树枝状晶体由体心立方（bcc）固溶体相和复杂的金属间化合物组成，而优化的合金是由蜂窝状树枝状晶体组成的，该蜂窝状树枝状晶体由处于铸造状态的单个bcc固溶体相组成。观察到均质化处理由于晶粒粗化而降低了等原子合金的断裂强度，尽管对硬度和其他机械性能影响很小。但是，均质化在不同程度上提高了优化合金的硬度和压缩屈服强度。经过优化的合金比等原子合金具有更好的塑性韧性，从而提高了其可加工性和抗辐射性。尽管它对硬度和其他机械性能影响很小。但是，均质化在不同程度上提高了优化合金的硬度和压缩屈服强度。经过优化的合金比等原子合金具有更好的塑性韧性，从而提高了其可加工性和抗辐射性。尽管它对硬度和其他机械性能影响很小。但是，均质化在不同程度上提高了优化合金的硬度和压缩屈服强度。经过优化的合金比等原子合金具有更好的塑性韧性，从而提高了其可加工性和抗辐射性。