Characterization of Ternary NiTiPt High-Temperature Shape Memory Alloys

摘要

Pt additions substituted for Ni in NiTi alloys are known to increase the transformation temperature of the alloy but only at fairly high Pt levels. However, until now ternary compositions with a very specific stoichiometry, Ni(50-x)Pt(x)Ti(50.9) have been investigated and then only to very limited extent. In order to learn more about this potential high-temperature shape memory alloy system, a series of twenty alloys along and on either side of a line of constant stoichiometry between NiTi were arc melted, homogenized, and characterized in terms of microstructure, transformation temperatures, and hardness. The resulting microstructures were examined by scanning electron microscopy and the phase compositions quantified by energy dispersive spectroscopy.