In situ study by synchrotron X-ray diffraction of the motion of basal stacking faults during the reverse-phase transformation of a Cu–Zn–Al single crystal

The reverse 9R→β transformation of a Cu–Zn–Al single crystal is followed ‘in situ’ by synchrotron X-ray topography and X-ray diffraction. From the modifications of the diffraction spots observed in Laue diagrams near the transition temperature, the motion and the elimination of basal stacking faults is described. This structural evolution of the crystal in the martensitic phase can be considered as a precursor stage to the 9R→β transformation.