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arXiv · 2009.05083

In-Situ Visualization of Long-Range Defect Interactions at the Edge of Melting

Leora E. Dresselhaus-Marais·Grethe Winther·Marylesa Howard·Arnulfo Gonzalez·Sean R. Breckling·Can Yildirim·Philip K. Cook·Mustafacan Kutsal·Hugh Simons·Carsten Detlefs·Jon H. Eggert·Henning Friis Poulsen
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Abstract

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.

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Leora E. Dresselhaus-Marais, Grethe Winther, Marylesa Howard, Arnulfo Gonzalez, Sean R. Breckling, Can Yildirim, Philip K. Cook, Mustafacan Kutsal, Hugh Simons, Carsten Detlefs, Jon H. Eggert, Henning Friis Poulsen. 2020-09-10. In-Situ Visualization of Long-Range Defect Interactions at the Edge of Melting. https://doi.org/10.1126/sciadv.abe8311

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