Fe-SMA–Based Shear Panel Damper: Solution Treatment, Design, and Seismic Performance

This study introduces a new type of shear panel damper that utilizes iron-based shape memory alloy (Fe-SMA) with enhanced low-cycle fatigue (LCF) resistance for structural damage control, with a particular focus on the effect of solution treatment on the properties of interest of Fe-SMA. Material-level investigation was conducted first, aimed at establishing a clear connection between microscopic structure and macroscopic properties, and to determine the most suitable solution treatment method for Fe-SMAs for structural damping purposes. This was followed by laboratory tests on a Fe-SMA based shear panel damper receiving an appropriate solution treatment, along with conventional metal shear panel dampers made of low yield point steel LYP225 and mild steel Q235. Results reveal that among the considered solution treatments, 1,100°C for 1 h leads to the most desired mechanical properties, such as lower yield stress, increased ductility, and longer LCF life, of Fe-SMA for seismic damping applications. The Fe-SMA shear panel damper demonstrates a significant improvement in LCF life and total energy dissipation capacity compared to traditional steel dampers. Finally, detailed numerical investigations were carried out to analyze the seismic response. A calibrated micromechanics-based model, i.e., cyclic void growth model, was employed to predict the fracture initiation of the Fe-SMA shear panel damper under seismic loading. This approach achieved reasonable accuracy, assisting in understanding the distinctive behavior of Fe-SMA shear panel dampers.