NiTi Shape memory alloys are attractive materials for a wide range of smart designs and innovative applications due to their fantastic functional properties. They can recover their pre-shape after significant deformation through temperature or stress change. NiTi Shape memory alloys are using as actuators, sensors, and structure in a wide range of application such as biomedical and robotic.

In this project, Shape memory behavior of NiTi bi-layer composite and single-layers were investigated using loading-unloading test and in-situ thermal cycling by applying electrical current. Furthermore, Shape Memory Recording Device along with digital camera was developed to evaluate the shape memory behavior of the pulled bi-layer specimens by tensile machine.

Results indicated that shape memory behavior improved in bi-layer specimens in comparison to single-layer. Also, the frequency response of the bi-layered specimens enhanced due to the composite effect of Martensitic and Austenitic layers. Also, the bi-later specimens could act as functionally-graded materials (FGM) due to their chemical composition gradients, and actuate in a broad range of temperatures.

In addition, The results demonstrated that the analytical model predictions were in a good agreement with the experimental observations as well as with the Finite Element Method (FEM) studies.