Structural analysis of the dynamic response of a shape memory alloy based damper.

Shape memory alloys (SMAs) are promising candidates for use in sensors, actuators, or passive dampers. This paper investigates the dynamic response of a superelastic NiTi holed disk to assess its damping performance relative to frequency and temperature for SMA-based damper applications. This study involved several key steps. Initially, the superelastic behavior of the SMA was experimentally characterized through tensile tests. This testing campaign provided the required data to identify material parameters of a thermomechanical constitutive model, already implemented in the finite element code Abaqus. Using the identified parameters, a finite element based structural analysis was conducted to predict the disk's operational range, ensuring it remained within the superelastic domain without incurring potential damage. Following this static analysis, a dynamic mechanical analysis (DMA) was performed on the disk. By employing a complex stiffness approach, we further examined the disk's damping effects. This dynamic method enabled a detailed description of the apparent stiffness and damping characteristics based on solicitation frequency, test temperature, vibration amplitude, and a predefined static displacement. The results indicated a clearly predominant structural effect over the phase transformation effect, despite the disk's substantial damping potential. [ABSTRACT FROM AUTHOR]