Processing and dielectric properties of (Pb,Bi)(Mg,Nb,Ti)O3 ceramics

Powders of the Pb(Mg1/3Nb2/3)O3–Bi(Mg2/3Nb1/3)O3 (PMN–BMN) system with PbTiO3 (PT) substitution levels of 20 and 30 mol% were prepared by a B-site precursor method. Phase development as well as dielectric properties were examined. Two major phases, i.e., MgNb2O6 and [(Mg1/3Nb2/3)1/2Ti1/2]O2 (with small fractions of Mg4Nb2O9), developed in the B-site precursor compositions, whereas only monophasic perovskite formed after the addition of PbO/Bi2O3. Maximum dielectric constant values of the two systems decreased rapidly with increasing BMN concentration, but corresponding temperatures were lowest at intermediate compositions.