A lead-free high-Curie-point ferroelectric ceramic, CaBi2Nb2O9

A lead-free high-Curie-point Aurivillius-phase ferroelectric ceramic, CaBi2Nb2O9, has been fabricated by spark plasma sintering (SPS). It has a Curie point (943 degrees C) that is much higher than previously reported (650 degrees C). The piezoelectric constant d(33) of the SPS textured material was nearly three times that of ordinary-fired (OF) materials and was stable up to 800 degrees C (see Figure). These textured ceramics are promising candidates for high-temperature piezoelectric applications.