Leora Dresselhaus-Marais1,2,Can Yildirim3,Philip Cook3,Henning Poulsen4,Jon Eggert5,Grethe Winther4,Mustafacan Kutsal4,Carsten Detlefs3,Hugh Simons4
Stanford University1,SLAC National Accelerator Laboratory2,European Synchrotron Radiation Facility3,Technical University of Denmark4,Lawrence Livermore National Laboratory5
Leora Dresselhaus-Marais1,2,Can Yildirim3,Philip Cook3,Henning Poulsen4,Jon Eggert5,Grethe Winther4,Mustafacan Kutsal4,Carsten Detlefs3,Hugh Simons4
Stanford University1,SLAC National Accelerator Laboratory2,European Synchrotron Radiation Facility3,Technical University of Denmark4,Lawrence Livermore National Laboratory5
Dislocation boundaries dominate the multiscale structure and properties of metals, setting the complex dynamics that determine how they respond to external stresses or heating. Recovery during thermal annealing leads to dislocation annihilation, self-organization and coarsening of dislocation structures through mechanisms that are poorly understood at the single-dislocation level – especially deep inside bulk materials. I present a new view of how dislocation boundaries migrate, evolve and destabilize over the course of thermal annealing, using the novel time-resolved dark-field X-ray microscopy (DFXM). With a 3D map of the dislocation structures and corresponding movies of the long-range dislocation motion and interactions, I map out how these dynamics over hundreds of micrometers cause these 3D structures to migrate and dissolve at temperatures >0.9 <i>T<sub>m</sub></i>, illustrating how stochastic thermal motion drives the high-T recovery.