The effect of twinning interactions up to the seventh generation on the evolution of microstructure
- 87 Downloads
The investigation reported here extends the conventional approach to the study of the interface network, by consideration of Σ3 n values up to n = 7 in alpha-brass. All 24 crystallographically-related solutions for each Σ3 n misorientation are included. The study has shown that multiple annealing twinning does not result in aggregation of higher Σ3 n values and concomitant reduction in Σ3s. When a 5° deviation from the exact reference misorientation was used, 20% and 27% of the interface length was Σ729 and Σ2187 respectively. This is a consequence of the increasing number of Σ3 n variants as n increases. Interactions of Σ3 n , often Σ3 + Σ3 n ↔Σ3 n +1, were observed frequently in the microstructure. The prevalence of boundaries near to high order Σ3 n attests their importance in the evolution of microstructure. Analysis of all 24 equivalent solutions for Σ3 n boundaries has shown that approximately half of these are misoriented on \(\langle 110\rangle\), compared to less than one-third on \(\langle 111\rangle\). The promulgation of Σ3 n boundaries via multiple twinning interaction events promotes and increases the proportion of \(\langle 110\rangle\) tilt boundaries, and to a lesser extent \(\langle 111\rangle\) boundaries. These misorientations have been shown to be associated with low-index boundary planes, and therefore multiple twinning is instrumental in promoting these ‘special’ planes.
KeywordsTriple Junction Interface Network Coincidence Site Lattice Twist Boundary Tilt Boundary
Unable to display preview. Download preview PDF.
- 2.V. Y. GERTSMAN and C. H . HENAGER, Inter. Sci. 11 (2003) 403.Google Scholar
- 5.V. Y. GERTSMAN, in Science and Technology of Interfaces, edited by S. Ankem, C. S. Pande, I. Ovid’ko and S. Ranganathan (TMS, 2002) p. 387.Google Scholar
- 6.V. RANDLE, Scripta Mater (in press).Google Scholar
- 7.V. RANDLE and H. M. DAVIES, Mater. Trans. A 33 (2002) 1853.Google Scholar
- 11.K. L. MERKLE and D. WOLF, Philos. Mag. A 65 (1992) 513.Google Scholar
- 12.U. WOLF, F. ERNST, T. MUSCHIK, M. W. FINNIS and H. F. FISCHMEISTER, ibid. 66 (1992) 991.Google Scholar