Titanium (Ti) and its alloys are attractive for a wide variety of structural and functional applications owing to excellent specific strength, toughness and stiffness, and corrosion resistance. However, if exposed to hydrogen sources, these alloys are susceptible to hydride formation in the form of TiH_x (0 < x ≤ 2), leading to crack initiation and mechanical failure due to lattice deformation and stress accumulation. The kinetics of the hydriding process depends on several factors, including the critical saturation threshold for hydrogen within Ti, the specific interaction of hydrogen with protective surface oxide, the rates of mass transport, and the kinetics of nucleation and phase transformation. Unfortunately, key knowledge gaps and challenges remain regarding the details of these coupled processes, which take place across vast ranges of time and length scales and are often difficult to probe directly. This work reviews recent advances in multiscale characterization and modeling efforts in Ti hydriding. We identify unanswered questions and key challenges, propose new perspectives on how to solve these remaining issues, and close knowledge gaps by discussing and demonstrating specific opportunities for integrating advanced characterization and multiscale modeling to elucidate chemistry and composition, microstructure phenomena, and macroscale performance and testing.

由于优异的比强度、韧性和刚度以及耐腐蚀性，钛 (Ti) 及其合金在各种结构和功能应用中具有吸引力。_{然而，如果暴露于氢源，这些合金很容易以 TiH x}的形式形成氢化物(0 < x ≤ 2)，由于晶格变形和应力积累导致裂纹萌生和机械故障。氢化过程的动力学取决于几个因素，包括 Ti 中氢的临界饱和阈值、氢与保护性表面氧化物的特定相互作用、传质速率以及成核和相变的动力学。不幸的是，关于这些耦合过程的细节，关键的知识差距和挑战仍然存在，这些过程发生在广泛的时间和长度范围内，并且通常难以直接探索。这项工作回顾了 Ti 氢化的多尺度表征和建模工作的最新进展。我们确定未解决的问题和关键挑战，就如何解决这些遗留问题提出新的观点，