金属玻璃的结构松,再生和可塑性:来自无弹性松光谱的微观细节
Michael Atzmon1,2, Jong Doo Ju3, Tianjiao Lei4
1Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109, USA.
Materials (Basel, Switzerland)
|December 9, 2023
概括
金属玻璃由于缺乏秩序,因此具有独特的特性. 这项研究揭示了剪切转换区的原子量化层次结构,为它们的行为提供了微观的见解.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 金属玻璃缺乏周期性和远程顺序,使物质建模复杂化.
- 传统的放松模型与拉伸的指数是不一致的,缺乏微观细节.
研究的目的:
- 为了研究金属玻璃的微观特性.
- 开发一个更准确的放松动态模型.
主要方法:
- 利用准静态无弹性放松来获得广泛的放松时间光谱 (>10个数量级).
- 分析了剪切转换区 (STZ) 的分布和特性.
主要成果:
- 获得了几个金属玻璃的详细放松时间光谱.
- 揭示了剪切转换区域的原子量化层次结构.
- 提供了对结构性放松,再生,可塑性和α/β放松机制的见解.
结论:
- 准静态无弹性放松方法为了解金属玻璃的行为提供了一个强大的工具.
- 确定STZ的层次结构为解释关键材料特性提供了微观的基础.
相关概念视频
Plastic Behavior
198
A material's elastic behavior is characterized by the disappearance of stress once the load is removed, allowing the material to return to its original state. However, when stress surpasses the yield point, yielding commences, marking the onset of plastic deformation or permanent set. This change from elastic to plastic behavior is influenced by the peak stress value and the duration before the load is removed. An intriguing observation occurs when a specimen is loaded, unloaded, and...
198
Atomic Nuclei: Types of Nuclear Relaxation
304
Nuclear relaxation restores the equilibrium population imbalance and can occur via spin–lattice or spin–spin mechanisms, which are first-order exponential decay processes.
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers...
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers...
304
Stress-Strain Diagram - Ductile Materials
728
The stress-strain relationship in ductile materials such as structural steel or aluminium is intricate and progresses through several stages. When a specimen is loaded, it initially exhibits a linear length increase, depicted by a steep straight line on the stress-strain diagram. It indicates the material is elastically deforming and will return to its original shape once unloaded. However, when a critical stress value is reached, plastic deformation begins. This stage sees substantial...
728


