A review on additive manufacturing of piezoelectric ceramics: From feedstock development to properties of sintered parts

Piezoelectric ceramics are extensively used in several engineering applications in the field of sensors, actuators, energy harvesting, biomedical, and many more. Traditional ways of manufacturing piezoelectric devices result in better piezoelectric/ferroelectric performance. However, they are restricted to only simple shapes. With the widespread influence of additive manufacturing (AM), it is now possible to fabricate complex structures which were not possible by conventional technologies. In order to fabricate such complex structures with precision, it is necessary to understand in detail the factors influencing the feedstock preparation and the challenges associated with different AM technologies. With an emphasis on the most commonly used AM techniques (direct ink writing, fused filament fabrication, vat photopolymerization, binder jetting, and selective laser sintering) for fabricating ceramic parts, this review paper intends to provide a deep insight into the factors affecting the feedstock preparation as well as post-processing conditions required to develop a high-performance piezoelectric device. The summarized tables detailing the various piezoelectric ceramic compositions and additives or ingredients used in formulating a printable feedstock, along with the optimum printing and post-processing conditions, will aid the readers in developing their own printable formulations and determining the best post-processing parameters to achieve the best performance out of the fabricated piezoelectric device. The advantages and disadvantages of the AM technologies are analyzed with specific reference to piezoceramic materials and the remaining challenges that require further research are emphasized. Furthermore, with the ongoing and continuous developments in additive manufacturing of piezoelectric materials, it is expected that such advancements will progressively transition towards commercialization, with the ultimate goal of widely incorporating additively manufactured devices into practical applications.