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

Journal Article · Mon Sep 14 04:00:00 EDT 2020 · arXiv.org

OSTI ID:1734735

Howard, Marylesa ^[1]; Gonzalez, Arnulfo ^[1]; Breckling, Sean ^[1]

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1. Mission Support and Test Services, LLC, North Las Vega, NV (United States)

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.

• Research Organization: Nevada National Security Site/Mission Support and Test Services LLC; Las Vegas, NV (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: NA0003624
• OSTI ID: 1734735
• Report Number(s): DOE/NV/03624--0762; STIP WF-20041048
• Journal Information: arXiv.org, Journal Name: arXiv.org
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE