x(0.94PbZn1/3Nb2/3O3 þ 0.06BaTiO3) þ (1 x)PbZryTi1yO3 where x ¼ 0.5, y ¼ 0.52 (abbreviated as PBZNZT) and the lead-free ceramics are (Bi0.5(Na1xKx)0.5)TiO3 where x ¼ 0.18 (abbreviated as BNKT),
x(0.94PbZn1/3Nb2/3O3 þ 0.06BaTiO3) þ (1 x)PbZryTi1yO3 where x ¼ 0.5, y ¼ 0.52 (abbreviatedas PBZNZT) and the lead-free ceramics are (Bi0.5(Na1xKx)0.5)TiO3 where x ¼ 0.18 (abbreviated asBNKT),