Copper based shape memory alloys have received much focus in recent times because of their good ductility, ease of production and processing and low cost. Earlier investigations have shown that ductility and other mechanical properties of the Cu-Al based shape memory alloys can significantly be improved by adding ternary elements such as Ni and Mn. While Cu-Al-Ni shape memory alloys have better thermal stability and higher operating temperatures, their practical applications are limited because of their poor workability. Cu-Al-Mn shape memory alloys on the other hand, have good ductility and workability, but their operating temperatures are lower. A similar approach is followed in Ni-Al alloys to overcome their brittleness by the addition of Fe. There is paucity of literature on the role of ternary addition of Fe to Cu-Al shape memory alloys. In the present work, therefore, the effect of aluminium and iron on the transformation temperatures has been studied. As the aluminium content increases the transformation temperatures decrease, while the ternary addition of Fe increases the transformation temperatures. The results are presented and discussed in detail in the paper.

The effect of alloying Cu-Al alloys with Fe on their transformation temperatures and shape memory properties was investigated by differential scanning calorimetry and bend test. It was found that the minor additions of iron resulted in change of transformation temperatures and led to excellent shape memory properties of the alloys. Since the transformation temperatures are high, they are an ideal choice for hightemperature applications.

Four shape memory alloys of Cu-Zn-Ni, in the range of 35 -55 wt% of Cu, 43 -60 wt% Zn and 2 -9 wt% Ni, were prepared by ingot metallurgy route in an induction furnace under an inert atmosphere. The shape memory effect was tested by bend test. The alloys were further tested for its corrosion behavior in fresh water, Hank's solution and sea water. From the results it was observed that the alloys exhibit high corrosion resistance in fresh water when compared to Hank's solution and sea water. And it was also observed that the alloys exhibit better corrosion resistance in Hank's solution than in sea water.

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