Report
Unraveling strongly entropic effect on beta-relaxation in metallic glass: Insights from enhanced atomistic samplings over experimentally relevant timescales
| العنوان: | Unraveling strongly entropic effect on beta-relaxation in metallic glass: Insights from enhanced atomistic samplings over experimentally relevant timescales |
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| المؤلفون: | Yang, Yi-Bo, Yang, Qun, Wei, Dan, Dai, Lan-Hong, Yu, Hai-Bin, Wang, Yun-Jiang |
| بيانات النشر: | AMER PHYSICAL SOC |
| سنة النشر: | 2020 |
| المجموعة: | IMECH-IR (Institute of Mechanics, Chinese Academy of Sciences) / 中国科学院力学研究所机构知识库 |
| مصطلحات موضوعية: | ENERGY LANDSCAPE, SECONDARY RELAXATIONS, MECHANICAL-BEHAVIOR, SUPERCOOLED LIQUIDS, DEFORMATION, DYNAMICS, PLASTICITY, SIGNATURES, DIFFUSION, Materials Science, Physics, Multidisciplinary, Applied, Condensed Matter |
| الوصف: | The Johari-Goldstein secondary (beta) relaxation is an intrinsic feature of glasses, which is crucial to many properties of disordered materials. One puzzling feature of beta-relaxation is its wide relaxation peak, which could imply a critical role of entropy. Here we quantify the activation entropy related to the beta-relaxation in metallic glass via well-tempered metadynamics simulations. The activation free energy of the beta-relaxation drastically decreases with increasing temperature, indicating a strongly entropic effect that may contribute a multiplication prefactor up to several orders of magnitude to the frequency. We further argue the entropic effect by linear extrapolation of the temperature-dependent activation free energy to 0 K, which gives rise to activation energy, in agreement with the barrier spectrum explored by the activation-relaxation technique. The entropic effect signifies the multiplicity of activation pathways which agrees with the experimentally found wide frequency domain of the beta-relaxation. |
| نوع الوثيقة: | report |
| اللغة: | English |
| Relation: | PHYSICAL REVIEW B; http://dspace.imech.ac.cn/handle/311007/85524 |
| DOI: | 10.1103/PhysRevB.102.174103 |
| الاتاحة: | http://dspace.imech.ac.cn/handle/311007/85524 https://doi.org/10.1103/PhysRevB.102.174103 |
| رقم الانضمام: | edsbas.C66F7312 |
| قاعدة البيانات: | BASE |
| DOI: | 10.1103/PhysRevB.102.174103 |
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