Experimental and Finite Element Analysis of Superelastic Behaviour of Shape Memory Alloy for Damping Applications

Shape Memory Alloys (SMAs) are good candidates for being used as passive dampers, strain sensors, stiffness or shape drivers. They present a low stiffness due to large reversible transformation strains. This communication presents the analysis of superelastic behaviour of both SMAs devices, typically used for damping applications: helicoïdal springs and Belleville washers. In a first part, experimental compression tests and particularly the influence of the amplitude and the loading rate are carried out. To do this, a specific tool adapted on the tensile test machine Zwick/Roell has been developed. In a second part, the finite element code Abaqus® made possible the numerical analysis thanks to its user-subroutine UMAT. It allowed to implement a developed thermo-mechanical non linear constitutive model describing all the specificities of SMAs. This model was adopted for the analysis of this finite element analysis. Thus, numerical investigations were leaded and compared with the experimental tests. Finally, an original modeling of the damping effect based on the equivalent complex stiffness is proposed. This modelling also leaded to the prediction of the dynamic behaviour of such SMAs devices, by solving the vibration equation.