Phenomena due to strain coupling in phase transitions

A theoretical model of an order-disorder phase transition in a crystal has been developed with strain-induced coupling between Ising spins. Strain coupling leads to long-ranged renormalized interactions between the spins which result in ferroelastic-antiferroelastic phase transitions. Computer simulations show textured microstructures evolving for some cases, similar to tweed textures. In other cases the long correlation length of strain suppresses nucleation, and the rate of (dis)ordering follows mean-field theory, very different from ``nucleation and growth.''