Study of dielectric and piezoelectric properties of Pb(Ni,Nb)O3– Pb(Zr,Ti)O3 ceramics using mechanically activated powder

Pb(Ni,Nb)O3–Pb(Zr,Ti)O3 of perovskite structure has been successfully prepared by mechanically activating mixed oxides of PbO, NiO, Nb2O5, ZrO2 and TiO2. This novel technique skips calcination steps at an intermediate temperature, which is otherwise required in both the conventional solid state reaction and chemical routes. Ceramics prepared by this process exhibits high diffusivity and sinterability. The measured density of the sintered pellets was found to be within 97–98% of their theoretical value. The room temperature dielectric constant (e¢) of ~4,500 and a loss (tand) of ~0.025 were measured on these samples. The high value of planar coupling factor, kp = 66% and charge coefficient, d33 = 660pC/N were obtained for the ceramic specimen sintered at 1,150 C. The maximum strain realized by the present system was ~0.3%.