Recently, flexible pressure sensors featuring enhanced sensitivity and durability through nano/micro additive manufacturing have been employed in various fields, including medical monitoring, E-skin technology, and soft robotics. This study focuses on the fabrication and verification of an interdigitated electrode (IDE) based flexible pressure sensor that incorporates microstructures, utilizing a direct patterning-based additive process. The IDE-patterned sample was designed with a total size of 7.95 × 10 mm2, a line width of 150 µm, a spacing of 200 µm, and a probe pad measuring 1.25 × 2 mm2. It was fabricated using AgNP ink on a primed 100 µm thick polyethylene naphthalate (PEN) substrate. The electrode layer was subsequently covered with a sensing layer made of a MWCNT/Ecoflex composite material, resulting in the final pressure sensor sample. Measurements indicated that the sensor exhibited good sensitivity and response speed, and it was confirmed that further improvements in sensitivity could be achieved by optimizing the size, spacing, and height of the microstructures. Building on the flexible pressure sensor structure developed in this study, we plan to pursue future research aimed at fabricating array sensors with integrated circuits and exploring their applicability in wearable devices for pressure sensing and control functions.

The purpose of this study was to investigate the springback behavior of magnesium alloy (AZ31B) at high temperature with respect to the holding time in the die-set. The changes of microstructure in the springback during V-Bending were analyzed. The springback of the magnesium alloy sheet showed a tendency to decrease as the forming temperature and the retention time in the die increase. In the microstructure analysis, there was minimal change in the microstructure at room temperature, while at high temperature the microstructure changed markedly. The increasing material holding time in die has been shown to reduce springback from internal energy reduction because of recrystallization and grain growth at high temperature.