DMA characterization of shape memory alloys
|Stefano Besseghini , Elena Villa|
Istituto per l'Energetica e le Interfasi Consiglio Nazionale delle Ricerche Unità di Lecco (IENI Lecco), Corso Promessi Sposi, 29, Lecco 23900, Italy
It is a know fact that the NiTi shape memory alloys have strong dependence of its special properties from the microstructure and its thermomechanical state. The DSC and mechanical test stress-strain vs temperature give many informations on the transformation temperature and on the pseudoelastic effect but the DMA analyzer is able to investigate all the transition effects, because it is possible to study the transition temperature in both stressed and unstressed condition over a wide temperature range (-160C; 600 C). Moreover the dynamic experiments allow us to analyse the linear mechanical response and the viscoelastic properties in different ranges of strain and frequency. In this work we measure the response of NiTi material in all the phases: austenite, romboedral and martensite. We test the material to different frequencies and in temperature ramp dynamic experiments. The NiTi alloy chosen is a Ni50.2Ti in a ribbons shape of 11x0.5x50 mm size, after two different thermal treatment: 400 C 30‘ and 750 C 10’.
Presentation: poster at E-MRS Fall Meeting 2005, Symposium C, by Stefano Besseghini
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-05-23 09:39 Revised: 2009-06-07 00:44