Effect of thermomechanical processing on grain boundary characteristics in two-phase brass

Commercial 60Cu–40Zn two-phase α–β′ alloy was thermomechanically processed to enhance the special low CSL boundaries. Repeated cycles of cold rolling (20%) and heat treatment (680°C/20min) resulted in an increase in Σ3 boundaries in the α phase that were identified as the annealing twins in the Electron Backscattered Diffraction analysis. The identical processing, however, produced a high frequency of low angle boundaries within the β′ phase. Formation of annealing twins in the α phase was accompanied by randomization of the texture of the starting material. The present result demonstrates the effectiveness of this thermomechanical processing in promoting annealing twins in the fcc α phase compared to the bcc β′ phase of commercial brass.