Study of precipitate formation in Cu-Al-Ni-Mn-Fe shape memory alloys


STANCIU S., BUJOREANU L. -. , Özkal B. , Öveçoğlu M. L. , Sandu A. V.

JOURNAL OF OPTOELECTRONICS AND ADVANCED MATERIALS, cilt.10, ss.1365-1369, 2008 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 10 Konu: 6
  • Basım Tarihi: 2008
  • Dergi Adı: JOURNAL OF OPTOELECTRONICS AND ADVANCED MATERIALS
  • Sayfa Sayıları: ss.1365-1369

Özet

The paper analyses the precipitation of Y-2 phase within the Y-1' thermally induced martensitic matrix of five Cu-Al-Ni-Fe-Mn shape memory alloys (SMAs), by means of differential scanning calorimetry (DSC) thermograms, optical microscopy (OM) and scanning electron microscopy (SEM). It has been proved that the flat exothermic peaks, occurring during the heating of martensitic specimens, correspond to the formation of Y-2 phase precipitates, which are characterized by two specific morphologies, with dendrite arms at about 90 degrees and a120 degrees, respectively. In spite of the presence of Y-2 phase precipitates, the occurrence of thermal memory has been emphasized, characterized by shape recovery degrees higher than 96 %.