Modular lead-free piezoceramic/polymer composites with locally adjustable piezoelectric properties

Lead-free piezoceramics are gaining interest in the field of bone tissue engineering due to their surface charges and improved bone cell adhesion. However, monolithic materials are less suitable for more complex medical conditions, as the properties must be tailored and locally adaptable. Therefore, we designed a modular composite of ceramic building blocks and polymer-matrix to customize the piezoelectric properties with individual polarization of each block, while maintaining the benefits of each phase. Barium titanate building blocks were prepared by injection molding and were assembled into 2-2-layered and modular structures, which were bonded with barium titanate-filled (ΦP = 35 vol %) epoxy resin. The piezoelectric response was determined using direct excitation via Berlincourt method, and the influence of the matrix thickness as well as the different polarization orientations of individual building blocks was investigated.