Evidence for Solute Drag during Recrystallization of Aluminum Alloys
نویسندگان
چکیده
Evidence of both solute drag as well as differences in migration mechanisms of certain boundary types has been found for an Al-Zr alloy. In-situ Transmission Electron Microscopy (TEM) annealing experiments coupled with Scanning Transmission Electron Microscopy (STEM) showed a stark contrast between Zr segregation at small and large scales. Specifically, Zr was found to segregate to, as well as precipitate at boundaries of grains smaller than 2 microns, whereas less segregation and no precipitation was found at large grains sizes, or long annealing times. Motivated by these results and those previously obtained by Orientation Imaging Microscopy (OIM), Local Electrode Atom Probe Microscopy with an ImagoTM LEAP microscope, was used to determine the concentrations of Zr and Al ions at grain boundaries; the results confirmed those from the STEM.
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In-Situ Quantification of Solute Effects on Grain Boundary Mobility and Character in Aluminum Alloys During Recrystallization
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