高熵合金辐照硬化与力学性能研究

高熵合金由于多主元元素混合引起高熵结构效应，使其具有优异的物理、力学和化学特性，如高强度、高耐磨性、耐蚀性、热稳定性、优异的抗辐照性能等。然而，辐照诱发高熵合金材料的硬化行为和力学性能预测仍缺少相关研究，严重地限制了对其长期服役后材料性能的评估。基于晶体塑性理论结合实验结果，研究了空洞形状依赖的硬化行为、位错环诱发的硬化行为以及氧化物弥散增强的高熵合金力学性能。研究发现，考虑多面体空洞与位错的概率依赖的空间交互作用，能够更加准确地预测辐照金属的屈服应力；晶格畸变对屈服强度，有着重要的贡献；氧化物弥散相对位错运动起强烈钉扎的作用，从而对强度产生影响，直接决定抗辐照性能。高熵合金作为一种具有综合优异力学性能的新型结构材料，在先进核能系统中有望被广泛应用，比如核反应堆的核燃料包壳管。

Irradiation hardening and mechanical properties of high entropy alloy

The multi principal element alloy forms a simple phase structure due to high entropy effect, resulting in excellent properties, such as, high strength, high wear resistance, corrosion resistance, thermal stability, and excellent radiation resistance. However, the prediction of mechanical properties of high entropy alloy induced by irradiation is still lack, which seriously limits the evaluation of its long-term service performance. Based on the crystal plasticity theory and experiment, the cavity-shape dependent hardening behavior, dislocation-ring induced hardening behavior and oxide dispersion enhanced mechanical properties in high entropy alloy are studied. The results show that the spatial interaction of polyhedral voids and dislocations in FCC metal is considered, and the yield stress of irradiated FCC metal is accurately predicted; lattice distortion has an important contribution to the yield strength; oxide dispersion plays a strong role in pinning the dislocation movement, thus affecting the strength and directly determining the radiation resistance. As a new type of structural material with comprehensive excellent mechanical properties, high entropy alloy is expected to be widely used in advanced nuclear power systems, such as nuclear fuel cladding tubes of nuclear reactors.