Abstract: The states inside the pseudoelastic hysteresis loop of CuZnAl single crystals are investigated by deformation controlled stress-strain measurements. The points that trigger the internal yield and recovery inside the pseudoelastic hysteresis loop dance a line that traverses the hysteresis loop from the upper left to the lower Tight corner. According to the thermodynamic arguments, we interpret that line as a line of unstable phase equilibrium. It is assumed that this line determines also the tendency for stress relaxation on the yield line and for a stress growth on the recovery line.

Key words: shape memory alloy, pseudoelastic hysteresis, CuZnAl