论文标题
在熔化边缘的远程缺陷相互作用的原位可视化
In-Situ Visualization of Long-Range Defect Interactions at the Edge of Melting
论文作者
论文摘要
将散装材料的微观缺陷与其宏观特性联系起来是材料科学中的一个古老问题。已知位错（线缺陷）之间的远距离相互作用在材料变形或熔体的方式中起关键作用，但我们缺乏将这些动力学连接到宏观特性的工具。我们引入了时间分辨的深色X射线显微镜，以直接可视化位错的移动和相互作用的数百微米内部，深度铝的深处。在实时电影的情况下，我们揭示了构成边界的热激活运动和位错的相互作用，并显示了在熔化温度的99％下，弱化的结合力如何不均匀地使结构不稳定。将微观结构的动力学连接到其稳定性，我们提供了重要的机会来指导和验证尚未经过测试的多尺度模型。
Connecting a bulk material's microscopic defects to its macroscopic properties is an age-old problem in materials science. Long-range interactions between dislocations (line defects) are known to play a key role in how materials deform or melt, but we lack the tools to connect these dynamics to the macroscopic properties. We introduce time-resolved dark-field X-ray microscopy to directly visualize how dislocations move and interact over hundreds of micrometers, deep inside bulk aluminum. With real-time movies, we reveal the thermally-activated motion and interactions of dislocations that comprise a boundary, and show how weakened binding forces inhomogeneously destabilize the structure at 99% of the melting temperature. Connecting dynamics of the microstructure to its stability, we provide important opportunities to guide and validate multiscale models that are yet untested.
