Effect of impurities on the recrystallization texture in commercially pure copper-ETP wires

This study investigates the effect of impurities, especially sulfur, on the recrystallization texture and microstructure of drawn copper-ETP wires (38% area reduction). Using neutron diffraction, we find that in all Cu samples the recrystallization texture is primarily composed of the 〈0 0 1〉//ND and 〈1 1 1〉//ND fiber components, regardless of impurity content. In addition, the recrystallization kinetics is slower, especially the incubation time is longer, when the S impurity content increases. In order to explain this phenomenon, the formation process of recrystallization texture – i.e. nucleation/growth sequences of the new grains – has been investigated in detail by means of TEM and EBSD. It is observed that grains with the 〈0 0 1〉//ND orientation nucleate first, by coalescence of dislocation cells close to highly disoriented grain boundaries, which suggests that sulfur impurities delay the process of recovery, necessary for nuclei formation, as well as the mobility of the grain boundaries during recrystallization.