Spontaneous twisting of the ferroelastic crystals below their Curie points

Using a torsion pendulum, the features of spontaneous twisting of several ferroelastic crystals at a temperature variation near the phase transition points have been studied as a function of a crystallographic orientation, a thermal and mechanical history, and an external static shear stress. It was assumed that a torque arises at the Curie point because of the specific domain structure organization resulted in the predominant formation of that certain domain types.