Raymond and Beverly Sackler Faculty of Exact Sciences, School of Physics and Astronomy, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel.
Molecules. 2020 Aug 7;25(16):3597. doi: 10.3390/molecules25163597.
Hydrogen can penetrate reversibly a number of metals, occupy the interstitial sites and cause large expansion of the crystal lattice. The question discussed here is whether the kinetics of the structural response matches hydrogen absorption. We show that thin Pd and CoPd films exposed to a relatively rich hydrogen atmosphere (4% H) inflate irreversibly, demonstrate the controllable shape memory, and duration of the process can be of orders of magnitude longer than hydrogen absorption. The dynamics of the out-of-equilibrium plastic creep are well described by the Avrami-type model of the nucleation and lateral domain wall expansion of the swelled sites.
氢气可可逆地渗透多种金属，占据间隙位置并导致晶格大幅膨胀。这里讨论的问题是结构响应的动力学是否与氢气吸收相匹配。我们表明，暴露于相对丰富的氢气环境（4% H）中的薄 Pd 和 CoPd 薄膜会不可逆地膨胀，表现出可控的形状记忆，并且过程的持续时间可以比氢气吸收长几个数量级。非平衡塑性蠕变的动力学可以很好地用肿胀部位的成核和横向畴壁扩展的 Avrami 型模型来描述。
