Experimental study of shape memory alloy plates under cyclic tension-compression loading scenarios

Shape memory alloys (SMAs) have garnered significant attention for their potential in earthquake-resistant structures, primarily due to their superelastic effect and exceptional self-centring capabilities. However, the mechanical properties of SMA plates, especially under cyclic tension-compression loading, remain underexplored. This research aims to bridge this gap by designing and testing 33 SMA plates equipped with bucklingrestrained devices. The study varied parameters such as specimen thickness (4 mm, 6 mm, and 8 mm), loading protocols (seven in total), and test temperatures (25 degrees C and 0 degrees C). The findings reveal that the stress-strain curves under cyclic tension-compression loading exhibited asymmetric characteristics. For instance, at 25 degrees C, a 4 mm thick specimen at 4% strain had a compressive peak stress that was 22.2% higher than its tensile counterpart, and its compressive residual strain exceeded the tensile residual strain by 99.0%. Furthermore, when compared to SMA plates under cyclic tension-release loading, those under cyclic tension-compression loading had reduced tensile residual strains. At 0 degrees C, the peak stress saw a decrease ranging from 2.4 to 43.1%, while the residual strain surged by 11.9-591.4% compared to the tests at 25 degrees C. This study provides novel insights into the behavior of SMA plates under varied conditions, emphasizing their potential for seismic applications.