Electromechanical Properties of Robocasted Barium Titanate Ceramics

This work presents the fabrication of dense polycrystalline barium titanate (BaTiO₃, BT) for electromechanical transduction using robocasting and cold isostatic pressing (CIP). The use of CIP as post-treatment is proposed to eliminate defects and increase the density of robocasted parts to improve the piezoelectric performance. For robocasting, pastes containing 50 and 52 vol% are developed; the resulting green robocasted parts are CIPed at 100 and 150 MPa. Using this proposed technique, samples robocasted with BT52 and CIPed at 150 MPa display a relative density of ≈98%, comparable with reference polycrystalline samples. In addition, an increase in both the piezoelectric charge and voltage coefficient is observed in robocasted parts, with the values up to 195 pC/N and 12 × 10⁻³ Vm N⁻¹, respectively. These values, which are comparable with previous studies of polycrystalline BT, indicate that the combined robocasting and CIP technique is a possible method for producing 3D printed piezoelectric sensors.