Self-ion irradiation-induced hardening behavior and microstructural evolution in dilute Zr-Nb alloys after exposure to low-dose irradiation have been investigated using nano-indentation measurement, EBSD analysis, and TEM examination. Two types of Zr-Nb alloys, i.e., solute-type Zr0.2Nb with only solute Nb atoms and precipitate-type Zr2Nb with both solute and excessive Nb atoms, are utilized to elucidate how the addition of Nb influences microstructural and mechanical property changes upon irradiation. Significant irradiation-induced hardening was confirmed for both alloys, and the extent of hardening was slightly greater in Zr2Nb relative to Zr0.2Nb. The irradiation-induced hardening at [0001] orientation exhibited the lowest value, which gradually intensified as the orientation deviated from [0001] axis to [$10\overline{1}0$] and $[2\overline{1}\overline{1}0]$ axes, irrespective of the concentration of Nb. This tendency is ascribed to the slip-system-dependent loops-dislocation interaction. The signs that the doping of Nb can suppress irradiation defect formation were evidenced by the strong sinking effects verified at the particle-matrix interface and grain boundary. With the application of the dispersed barrier hardening model and quantitative characterization of microstructure features, it is revealed that the <a>-loops are mostly responsible for the hardening in both alloys and a rational obstacle strength of <a>-loop in α-Zr is derived as ∼0.33-0.36.

使用纳米压痕测量，EBSD分析和TEM检查研究了低剂量辐照后稀Zr-Nb合金中自离子辐照引起的硬化行为和显微组织演变。两种类型的Zr-Nb合金，即仅具有溶质Nb原子的溶质型Zr0.2Nb和具有溶质和过量Nb原子的沉淀型Zr2Nb，被用于阐明Nb的添加如何影响合金的显微组织和力学性能变化。辐射。两种合金均确认到显着的辐射诱导硬化，并且相对于Zr0.2Nb，Zr2Nb的硬化程度略大。[0001]取向的辐照引起的硬化表现出最低值，随着取向从[0001]轴偏离为[[$10\overline{\mathrm{1个}}0$]和 $[2\overline{\mathrm{1个}}\overline{\mathrm{1个}}0]$轴，与Nb的浓度无关。这种趋势归因于与滑移系统有关的环-位错相互作用。Nb的掺杂可以抑制辐照缺陷形成的迹象由颗粒-基体界面和晶界处证实的强下沉效应证明。通过应用弥散势垒硬化模型和微观结构特征的定量表征，揭示了<a>环主要负责两种合金的硬化以及α- Zr中<a>环的合理障碍强度。得出约0.33-0.36。