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

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.

References in corpus (2)

• Direct Visualization of Dislocation Dynamics in Grain Boundary Scars
• Mirror Furnace for Synchrotron Dark Field X-ray Microscopy Experiments

Cited by in corpus (5)

• Harnessing dislocation motion using an electric field
• Simultaneous Bright- and Dark-Field X-ray Microscopy at X-ray Free Electron Lasers
• Dark Field X-ray Microscopy Below Liquid-Helium Temperature: The Case of NaMnO2
• Analytical Methods for Superresolution Dislocation Identification in Dark-Field X-ray Microscopy
• Automating Dislocation Characterization in 3D Dark Field X-ray Microscopy