Templated Grain Growth for High-Performance Lead-Free Piezoceramics

템플릿 기반 일방향 그레인 성장을 통한 고성능 무연 압전 세라믹 제조 연구 동향

As a new class of novel technologies for fabrication of piezoceramics, the templated grain growth (TGG) has been gaining tremendous attention due to the ability to align ferroelectric domains and thus improve piezoelectric properties, which are similar with the ones of single crystal. Towards the realization of textured grains in a specific direction, two-dimensional template materials should be preferentially needed with some specific conditions such as small lattice mismatch, similar crystal structure and composition compared to those of matrix piezoelectric ceramic powders. This mini review presents recent progress on TGG to provide highperformance textured (K,Na)NbO3 ceramics as an ideal lead-free to lead-based piezoceramics with a focus on the fabrication fundamentals and underlying mechanism. Additionally, some parameters related to the fabrication of green body during a tape casting are surveyed. Finally, we provide an insight into challenges and future directions in the TGG-based piezoceramics.