This work describes a macroscopic approach based on continuum mechanics to martensitic phase transformations in elastic crystalline solids. Such transformations are sudden phase transitions from austenite phase with higher symmetries to martensite phase with lower symmetries. A phase transition manifests itself as jumps in homogeneous deformation gradients across a planar surface of discontinuity. Deformation gradients consist only of pure stretch tensor, and their jumps are governed by well-known Hadamard conditions. These jump conditions, coupled with the minimization of total strain energy, are employed to study the formation of wedge-like microstructures from martensite to austenite which play an important role in the behaviour of shape-memory alloys and in the phenomenon of self- accomodation, in which martensite arranges itself in such a microstructure that there is no change in its macroscopic shape. For various crystal classes, the necessary and sufficient conditions for such formations are obtained and are associated with lattice parameters. Theoretical results are compared with available experimental data, and a rather good agreement is observed.
For the entire collection see [Zbl 0787.00039].