Feature of morphotropic phase boundary of yBiGaO3–(1−x−y)BiScO3–xPbTiO3 high-temperature piezoelectric ceramics

Abstract

y Bi Ga O 3 – ( 1 − x − y ) Bi Sc O 3 – x Pb Ti O 3 (BGSPT) ternary piezoelectric ceramics were fabricated by using conventional mixed oxide ceramic processing. It was found that the introduction of BiGaO3 into BiScO3–PbTiO3 system would cause a shift of morphotropic phase boundaries (MPBs), from x=0.64, y=0 to x=0.56, y=0.155; and an increase of Curie temperature (TC) near MPB, from 450 up to 494°C, respectively. BGSPT ceramics possessed higher TC (∼494°C) and high piezoelectric coefficient (d33∼180pC∕N), and showed the different rule of the Curie temperature near MPB versus the end member tolerance factor (t). The mechanism of higher TC in BGSPT system was also proposed.