Composition induced rhombohedral–tetragonal phase boundary and high piezoelectric activity in (K0.48,Na0.52) (Nb(1-x)Sbx)O3 - 0.05Ca0.2(Bi0.5,Na0.5) 0.8ZrO3 lead-free piezoelectric ceramics

Abstract New lead-free piezoelectric ceramics (K 0.48 ,Na 0.52 ) (Nb (1- x ) Sb x )O 3 −0.05Ca 0.2 (Bi 0.5 ,Na 0.5 ) 0.8 ZrO 3 (KNNS x -CBNZ) were fabricated by traditional solid-state sintering process. The effects of Sb content on phase structures and electrical properties of the KNNS x -CBNZ ceramics were studied. Because Sb 5+ can increase the rhombohedral-orthorhombic phase transition temperature and decrease orthorhombic-tetragonal phase transition temperature simultaneously, it is found that the ceramics in the composition range of 0.02 x x =0.03: d 33 =470 pC/N, k p =52.4%, e r =1563, tan δ =3.30% and T c =243 °C. The results show that KNNS x -CBNZ ceramics have potential applications for substituting the lead based piezoelectric ceramics.