1 Department of Energy Conversion and Storage, Technical University of Denmark2 Imaging and Structural Analysis, Department of Energy Conversion and Storage, Technical University of Denmark3 Materials science and characterization, Department of Wind Energy, Technical University of Denmark4 Department of Wind Energy, Technical University of Denmark5 Tsinghua University6 Tsinghua University
The deformed microstructure and recrystallization behavior of copper samples processed using equal channel angular extrusion (ECAE) have been investigated. The heavily deformed microstructure was found to be non-uniform through the sample thickness and to vary in a manner consistent with the non-uniform distribution of strain imposed by processing. The through-thickness heterogeneity of the deformed microstructure resulted in a different extent of recrystallization in different layers during annealing. Recrystallized grains were also observed in samples that were not annealed, but stored at room temperature, which indicates that the deformed microstructure of ECAE-processed pure copper is unstable even at room temperature. In each sample, recrystallization was found to initiate in regions containing predominantly large misorientations.
Materials Science Forum, 2012, Vol 715-716, p. 825-830