Yuan Xudong, Şopu Daniel, Song Kaikai, Eckert Jürgen
Erich Schmid Institute of Materials Science, Austrian Academy of Sciences, Jahnstraße 12, A-8700 Leoben, Austria.
Fachgebiet Materialmodellierung, Institut für Materialwissenschaft, Technische Universität Darmstadt, Otto-Berndt-Straße 3, D-64287 Darmstadt, Germany.
Materials (Basel). 2022 Feb 24;15(5):1702. doi: 10.3390/ma15051702.
One way to rejuvenate metallic glasses is to increase their free volume. Here, by randomly removing atoms from the glass matrix, free volume is homogeneously generated in metallic glasses, and glassy states with different degrees of rejuvenation are designed and further mechanically tested. We find that the free volume in the rejuvenated glasses can be annihilated under tensile or compressive deformation that consequently leads to structural relaxation and strain-hardening. Additionally, the deformation mechanism of highly rejuvenated metallic glasses during the uniaxial loading-unloading tensile tests is investigated, in order to provide a systematic understanding of the relaxation and strain-hardening relationship. The observed strain-hardening in the highly rejuvenated metallic glasses corresponds to stress-driven structural and residual stress relaxation during cycling deformation. Nevertheless, the rejuvenated metallic glasses relax to a more stable state but could not recover their initial as-cast state.
使金属玻璃恢复活力的一种方法是增加其自由体积。在此，通过从玻璃基体中随机去除原子，在金属玻璃中均匀地产生自由体积，并设计出具有不同恢复程度的玻璃态并进一步进行机械测试。我们发现，恢复活力的玻璃中的自由体积在拉伸或压缩变形下会消失，从而导致结构弛豫和应变硬化。此外，研究了高度恢复活力的金属玻璃在单轴加载-卸载拉伸试验中的变形机制，以便系统地理解弛豫和应变硬化之间的关系。在高度恢复活力的金属玻璃中观察到的应变硬化对应于循环变形过程中应力驱动的结构和残余应力弛豫。然而，恢复活力的金属玻璃会弛豫到更稳定的状态，但无法恢复其初始铸态。
