Preparations and characterizations of perovskite 0.80PMN-0.20PT ceramic by using a one-step calcination method

A relaxor ferroelectric ceramic, 0.80Pb(Mg1/3Nb2/3)O3-0.20PbTiO3 (0.80PMN-0.20PT) with a pyrochlore-free phase, was prepared by using a one-step calcination method. The precursors were prepared by adding an aqueous Mg(NO3)2·6H2O rather than MgO to the alcoholic slurry of PbO, TiO2 and Nb2O5. The TG-DSC and XRD analysis show that the mechanism in this method is different from those of the columbite method. The phase composition and electric properties of these ceramics were researched. For this ceramic, the maximum value of dielectric constant reaches 33 500, the remnant polarization is 19.2 μC/cm2.