Additive manufacturing of hybrid piezoelectric/magnetic self-sensing actuator using pellet extrusion and immersion precipitation with statistical modelling optimization

Additive manufacturing is a growing field of fast reliable processing as it can fabricate complex designs, both internally and externally. Multi-stimuli-responsive/-functional polymers can respond to numerous stimuli and execute multiple tasks. A thin flexible hybrid piezoelectric-magnetic self-sensing actuator (HPMSA) is printed utilizing pellet extrusion and immersion precipitation 3D printing (ip3DP) to enhance its performance as both a sensor and an actuator. Utilizing molecular interactions and pores created within the structure, ip3DP showcased a more stable and effective self-sensing actuator than pellet extruded samples. Additionally, HPMSA fabricated using either additive manufacturing methods had a higher overall crystal content of 62.1 % compared to the conventional process of compression molding and mechanical stretching, highlighting its scale-up fabrication whilst promoting piezoelectric crystals. For optimization, kernel ridge regression model was utilized to predict the optimal ip3DP condition, which was experimentally validated. As a vibration damper, the ip3DP HPMSA with an optimized geometry showcased an effective high voltage sensing output of 13 mV/g and maximum weighted damping of 1.8 m/s2, lowering passenger health risks to "caution zone" in high vibration environments. The thin and flexible HPMSA provides understanding into multi-stimuli/-functional materials, simultaneous alignment, and vibration control.