The growth and coalescence of microvoids nucleating in the second phase particles are the dominant mechanism of ductile fracture. The ductile fracture process is strongly influenced by the stress state. Based on a triaxiality dependent cohesive zone model, the ductile fracture process of zirconium alloys under different stress states is described in the present study. Under the condition of plane strain, a compact tension analysis configuration is established for hydrided zirconium alloys composed of matrix and hydrides. By comparing our prediction with the results based on the extended finite element method, we can calibrate model parameters and then verify the model. The results show that the presence of hydrides accelerates the crack propagation and decreases the post-peak load level. Moreover, we find that the fracture resistance of zirconium alloys is strongly affected by the length, arrangement, quantity, and spacing of the hydrides. Specifically, for hydrides with the length along the crack propagation path, the increase in their length enhances the peak load and reduces the corresponding boundary displacement. The increase in their quantity reduces the post-peak load level. Besides, the increase in their spacing enhances the boundary displacement corresponding to the sudden load drop. For the ductile fracture of zirconium alloys, these simulation results provide insights into their ability to resist crack propagation.

在第二相颗粒中成核的微孔的生长和聚结是韧性断裂的主要机制。韧性断裂过程受应力状态的影响很大。本研究基于三轴度相关内聚区模型，描述了不同应力状态下锆合金的韧性断裂过程。在平面应变条件下，建立了由基体和氢化物组成的氢化锆合金的紧凑拉伸分析构型。通过将我们的预测与基于扩展有限元方法的结果进行比较，我们可以校准模型参数，然后验证模型。结果表明氢化物的存在加速了裂纹扩展并降低了峰值后载荷水平。而且，我们发现锆合金的抗断裂性受氢化物的长度、排列、数量和间距的强烈影响。具体而言，对于沿裂纹扩展路径长度的氢化物，其长度的增加增强了峰值载荷并减少了相应的边界位移。它们数量的增加降低了峰值后的负载水平。此外，它们间距的增加增强了对应于突然负载下降的边界位移。对于锆合金的韧性断裂，这些模拟结果提供了对其抵抗裂纹扩展能力的见解。它们长度的增加增强了峰值载荷并减少了相应的边界位移。它们数量的增加降低了峰值后的负载水平。此外，它们间距的增加增强了对应于突然负载下降的边界位移。对于锆合金的韧性断裂，这些模拟结果提供了对其抵抗裂纹扩展能力的见解。它们长度的增加增强了峰值载荷并减少了相应的边界位移。它们数量的增加降低了峰值后的负载水平。此外，它们间距的增加增强了对应于突然负载下降的边界位移。对于锆合金的韧性断裂，这些模拟结果提供了对其抵抗裂纹扩展能力的见解。