Evolution of texture and grain boundary microstructure in two-phase (α + β) brass during recrystallization

Abstract

The evolution of texture and microstructure during recrystallization is studied for two-phase copper alloy (Cu–40Zn) with a variation of the initial texture and microstructure (hot rolled and solution treated) as well as the mode of rolling (deformation path: uni-directional rolling and cross rolling). The results of bulk texture have been supported by micro-texture and microstructure studies carried out using electron back scatter diffraction (EBSD). The initial microstructural condition as well as the mode of rolling has been found to alter the recrystallization texture and microstructure. The uni-directionally rolled samples showed a strong Goss and BR {236}⟨385⟩ component while a weaker texture similar to that of rolling evolved for the cross-rolled samples in the α phase on recrystallization. The recrystallization texture of the β phase was similar to that of the rolling texture with discontinuous ⟨101⟩ α and {111} γ fiber with high intensity at {111}⟨101⟩. For a given microstructure, the cross-rolled samples showed a higher fraction of coincident site lattice Σ3 twin boundaries in the α phase. The higher fraction of Σ3 boundaries is explained on the basis of the higher propensity of growth accidents during annealing of the cross-rolled samples. The present investigation demonstrates that change in strain path, as introduced during cross-rolling, could be a viable tool for grain boundary engineering of low SFE fcc materials.

Keywords:

• processing
• recrystallization
• texture
• X-ray diffraction
• EBSD

Acknowledgements

The work involved the use of facilities set-up at the Indian Institute of Science, Bangalore India under the Institute Nano-science Initiative as well as the Institute's X-ray facility. The authors also acknowledge Department of Science and Technology, Government of India for the facilities set up under the Institute's Nano-science Initiative. This project was initiated with the financial support from The Boeing Company, USA. The authors acknowledge the same.