Enhanced Strain Properties in KNN-Based Lead-free Piezoelectric Multilayer Actuators by Low-Temperature Texture Engineering

In response to the demand for lead-free replacement of multilayer piezoelectric actuators (MLAs), KNN-based lead-free piezoceramics with high curie temperatures and environmental friendliness are selected for the application study. To improve the piezoelectric properties of piezoelectric ceramics, a texture approach was adopted, and 0.2% CuO was added as a sintering aid; the TGG texturing technique was combined with the stacked element cofiring technique. Finally, we investigate the relevant properties of KNN-based multilayer piezoelectric actuators. Here, a compositional system of 0.96-(Na0.5K0.5)-(Nb0.965Sb0.035)-O3-0.01CaZrO3-0.03-(K0.5Bi0.5HfO3) (KNNS-KBH-CZ) was chosen to fabricate multilayer piezoelectric actuators. The texturing degree of KNNS-KBH-CZ/CuO reaches as high as 75%, leading to a high strain performance (strain of 0.14%, d 33* of 466 pm/V) under a low electric field (3 kV/mm), highlighting the potential application of KNN-based piezoelectric ceramics in the field of piezoelectric actuators.