Investigations of Solid Phase Processes in CuAlNi Base Shape Memory Alloys

Cu based Shape Memory Alloys are favored because of their high transformation temperatures and low extend their suitability, Mn and Fe were added to the base CuAlNi alloy in order to increase ductility. The ageing processes and the effect of the Mn and Fe addition were examined using differential scanning calorimetry, optical microscopy, scanning electron microscopy, transmission electron microscopy and in-situ optical microscopy. Transformation temperatures shifted to higher temperatures in the CuAlNi alloy as the ageing time was increased. In CuAlNiMn and CuAlNiMnFe alloys the thermoelastic martensitic transformation disappeared in the aged samples. known. The examinations were focused to characterize and identify this exothermic process.