Multifarious strategies for resolving the deep‐curing challenges of PZT piezoceramics slurry in vat photopolymerization

Abstract The vat photopolymerization (VPP) technology offers exceptional flexibility in design and manufaction of high‐performance piezoceramic structures. However, due to the high refractive index and strong UV absorption characteristics of Pb‐based ceramics, ceramic slurries are required to have a low solid content in for efficient deep‐curing. This limitation often results in sintering distortion, cracking, low density, and deteriorated piezoelectric properties. To address these challenges, a heat treatment process was initially employed to spheroidize the PZT powder, which effectively decreased light scattering and absorption. Subsequently, high‐refractive‐index and highly reactive photosensitive resins were introduced to enhance the penetration of UV light and reduce the critical exposure energy of the slurry. Additionally, a hindered amine light stabilizer is added to capture the peroxy radicals to overcome the oxygen inhibition effect and further increase the curing depth. As a result, a PZT slurry with a high solid content of 45 vol.%, was successfully formulated, facilitating the manufacturing of PZT ceramics with complex structures. The sintered samples achieved a high relative density of 96.5% and a d 33 value of 573 pC/N. These optimized strategies provide a solid foundation for the development of high‐performance PZT devices with intricate geometries.