The effects of externally imposed stresses on the phase separation process of elastically coherent binary-alloy systems were investigated numerically with large-scale Langevin simulations. Both two- and three-dimensional systems were considered. The intrinsic crystallographic symmetries of the system compete with the external strains in the determination of both the shapes and the orientation of the precipitates. These can go all the way from the configurations predicted by a stress-free equilibrium criterion at small stresses, to lamellar and cylindrical configurations (or stripe configurations in two dimensions) at high stresses. Between these two extremes, there are new shapes and a continuous spectrum of orientation angles. This competition can also induce late-time, large-scale splitting of the domains. The stress effect is larger when the precipitates form the majority phase, and considerably smaller when they are in the minority.
- Received 31 January 2000
- Revised 13 April 2000
- Published in the issue dated 1 August 2000
© 2000 The American Physical Society