Development of highly textured piezoelectric ceramics via templated grain growth

Textured polycrystalline piezoelectric materials are expected to provide improved properties compared to untextured ceramics, and low processing costs compared to single crystals. NexTech Materials is developing textured polycrystalline piezoelectric ceramics via Templated Grain Growth (TGG). In the TGG process, a number of large anisotropic template particles are oriented in a fine particle matrix in the green state, and grow during heat treatment, consuming the surrounding matrix grains and creating a crystallographically oriented ceramic. The keys to TGG processing are the development of the template and matrix components. Templates should be large, anisotropic and crystallographically isostructural with the matrix material. The matrix should be high surface area to provide sufficient driving force for densification and grain growth. The development of both components and their integration for the PMN-PT system be discussed