An anisotropic distribution of coherent precipitate variants may result in anisotropic behavior of a two-phase material. The distribution of the coherent precipitate variants can be controlled using constrained aging. This article reports our experimental and computational studies of the stress effect on the spatial arrangement of coherent precipitate variants. The research demonstrates that the anisotropic elastic coupling between applied stress/strain and the local strain caused by the lattice mismatch between different phases makes the growth of differently oriented phase variants selective. Ti11Ni14 precipitation in a Ti-51.5at.% Ni alloy was investigated as a particular example. It was demonstrated that the constrained aging strongly affected the distribution of Ti11Ni14 precipitate variants. The resulting selective variant growth of Ti11Ni14 precipitates can be predicted based on the symmetry analysis and the elastic energy calculation.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Physical and Theoretical Chemistry
- Metals and Alloys