Effects of WO3 addition on the structure and electrical properties of Pb3O4 modified PZT–PFW–PMN piezoelectric ceramics

The ceramics were prepared successfully by Pb3O4 and WO3 additions to 0.90Pb(Zr,Ti)O3–0.03Pb(Fe2/3W1/3)O3–0.07Pb(Mn1/3Nb2/3)O3 (0.90PZT–0.03PFW–0.07PMN). Effects of the additions on the structure, bulk density and electrical properties of ceramics were investigated. The results revealed that the proper additions of WO3 with 2.0 wt.% Pb3O4 excess could form liquid phase that promoted the densification of the ceramics. The fracture mode changed from transgranular to intergranular as increasing WO3 with 2.0 wt.% Pb3O4 excess. The piezoelectric and dielectric properties were also promoted by excess of Pb3O4 and WO3 additions. The optimized electrical properties were obtained at excess of 2.0 wt.% Pb3O4 and 0.15 wt.% WO3. The parameters were as follows: d33 = 351 pC/N, Kp = 0.64, Qm = 1882, ɛr = 1798, tan δ = 0.0052, Pr = 19.94 μC/cm2 and Ec = 11.98 kV/cm, which shows high Kp, Qm, d33 and low tan δ can be obtained simultaneously by adding WO3 addition to Pb3O4 modified PZT–PFW–PMN system.