The influence of thermo-mechanical treatments on TiNi shape memory alloys has been studied with Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Thermal Analysis (DMTA). The DSC is a widely used technique to study the transformation temperatures and the behaviour of TiNi alloys. Even though DMTA is a well-known technique, it is not so commonly used with this kind of materials. In this paper both techniques have been applied to TiNi strips subjected to different cycles of annealing, cold rolling and quenching. The aim of the work is to find and characterise the best thermo-mechanical treatment in TiNi thin sheets that controls the transformation temperature and the recovery force during constrained activation. The results of DSC and DMTA have been compared to find a correlation between the two different techniques that may allow the behaviour of a constrained shape memory alloy and the influence of an applied stress on the transformation temperatures to be studied.
Using DSC and DMTA for the study of thermo-mechanical treatments improving the transformational behavior of Ti-rich nitinol sheets
MERLIN, Mattia;
2010
Abstract
The influence of thermo-mechanical treatments on TiNi shape memory alloys has been studied with Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Thermal Analysis (DMTA). The DSC is a widely used technique to study the transformation temperatures and the behaviour of TiNi alloys. Even though DMTA is a well-known technique, it is not so commonly used with this kind of materials. In this paper both techniques have been applied to TiNi strips subjected to different cycles of annealing, cold rolling and quenching. The aim of the work is to find and characterise the best thermo-mechanical treatment in TiNi thin sheets that controls the transformation temperature and the recovery force during constrained activation. The results of DSC and DMTA have been compared to find a correlation between the two different techniques that may allow the behaviour of a constrained shape memory alloy and the influence of an applied stress on the transformation temperatures to be studied.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
