MRS Communications , 2015, 5 (1), 77-82.

Indentation-induced two-way shape-memory effect in aged Ti-50.9 at.% Ni

Frensemeier, Mareike | Arzt, Eduard | Qin, Enwei | Frick, Carl P. | Schneider, Andreas S.

In this study, Vickers indentation was used to investigate the two-way shape-memory effect (TWSME) in an austenitic Ti-50.9 at.% Ni alloy, exposed to different heat treatments. Three aging treatments were used to manipulate the size of Ti

3

Ni

4

precipitates. All samples were Vickers indented, and the indent depth was investigated as function of thermal cycling. The TWSME was found only in the material aged at 400 °C, which contained coherent precipitates. Thermal cycling shows stable TWSME, however, heating well above the austenite finish temperature lead to permanent austenitic protrusions. The results indicate that stabilized martensite plays a critical role in creating TWSME surfaces.

OPEN ACCESS Weiterlesen