Liu Yang, Wenman Mark R, Davies Catrin M, Dunne Fionn P E
Department of Materials, Imperial College London, London, SW7 2AZ UK.
School of Engineering, University of Leicester, Leicester, LE1 7RH UK.
J Mater Sci. 2025;60(14):6254-6287. doi: 10.1007/s10853-025-10796-8. Epub 2025 Apr 10.
This study focuses on the hydride precipitation in zirconium polycrystals during thermo-mechanical cycles. The precipitation and dissolution of mesoscale hydrides in Zircaloy-4 is modelled using crystal plasticity finite element methods supported with DFT-informed zirconium lattice hydrogen concentration. Results for a tri-crystal case show the effects of crystallography, thermo-mechanical load and elasto-plastic anisotropy on hydride nucleation and growth. Analyses of polycrystalline models provide new insights into the complex precipitation process of hydrides in Zircaloy-4 with explicit representation of experimental observations that lay the foundation for further research in this field. Micromechanical findings demonstrate the importance of microstructure, pre-thermal condition, and hydrogen concentration limit on hydride precipitation. Overall, the study provides a deeper understanding of hydride formation during industrially relevant reactor conditions.
本研究聚焦于热机械循环过程中锆多晶体中的氢化物析出。采用晶体塑性有限元方法，并结合基于密度泛函理论（DFT）的锆晶格氢浓度，对锆合金-4中细观尺度氢化物的析出和溶解进行建模。三晶体案例的结果显示了晶体学、热机械载荷和弹塑性各向异性对氢化物形核和生长的影响。多晶体模型分析为锆合金-4中氢化物复杂的析出过程提供了新见解，明确呈现了实验观察结果，为该领域的进一步研究奠定了基础。微观力学研究结果表明微观结构、预热条件和氢浓度极限对氢化物析出的重要性。总体而言，该研究加深了对工业相关反应堆条件下氢化物形成的理解。
