发表机构
University of Nevada, Reno; Rose-Hulman Institute of Technology（内华达大学里诺分校; 罗斯-赫尔曼理工学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过深度神经网络势和分子动力学模拟，发现氢稳定铁中{332}-{10 9 3}多模态孪晶网络并抑制去孪晶，导致后屈服硬化，揭示了中间相、氢和温度对孪晶路径和网络形成的控制作用。
AI 中文摘要
氢显著影响体心立方铁中的塑性，但其作用通常归因于位错介导的机制，导致氢对相变和变形孪晶的影响知之甚少。我们使用密度泛函理论训练的深度神经网络原子间势和大规模分子动力学来研究纯体心立方铁和含10%氢的铁。研究发现，氢降低了屈服应力，但更重要的是，增加了{112}孪晶变体的持久性并抑制了去孪晶。这种效应稳定了互连的{332}-{10 9 3}多模态孪晶网络，并产生了显著的后屈服硬化。较高的温度促进了初始转变，但削弱了高指数多模态孪晶网络的持久性。此外，孪晶遵循不同的载荷依赖路径：压缩通过共区和非同区孪晶-孪晶相互作用产生{332}和{10 9 3}边界，而拉伸通过非同区相互作用产生{7 4 1}边界。这些结果建立了一个基于路径的图像，其中中间相决定了可访问的孪晶模式和变体晶体学，而氢和温度控制着它们的动力学存活和高指数孪晶网络的出现。
英文摘要
Hydrogen significantly affects plasticity in bcc iron, but its role is commonly attributed to dislocation-mediated mechanisms, leaving the influence of hydrogen on phase transformation and deformation twinning poorly understood. We use a density-functional-theory-trained deep-neural-network interatomic potential and large-scale molecular dynamics to study pure bcc Fe and Fe containing 10% hydrogen. It is found that hydrogen lowers the yield stress but, more importantly, increases the persistence of {112} twin variants and suppresses detwinning. This effect stabilizes an interconnected {332}-{10 9 3} multimodal twin network and produces pronounced post-yield hardening. Higher temperature promotes the initial transformation but weakens the persistence of the high-index multimodal twin network. Moreover, twinning follows distinct loading-dependent pathways: compression generates {332} and {10 9 3} boundaries through co-zone and non-co-zone twin-twin interactions, whereas tension produces {7 4 1} boundaries through non-co-zone interactions. These results establish a pathway-based picture in which the intermediate phase determines the accessible twin modes and variant crystallography, while hydrogen and temperature control their kinetic survival and the emergence of high-index twin networks.
Comments33 pages, 8 figures, 1 table. Submitted to the International Journal of Plasticity
