PZN-PFW and PFN-PFW Relaxor Ferroelectric Ceramics by a Reaction-Sintering Process

Pb((Zn1/3Nb2/3)0.6(Fe2/3W1/3)0.4)O3 and Pb((Fe1/2Nb1/2)0.7(Fe2/3W1/3)0.3)O3 (PZNFW and PFNW) perovskite ceramics prepared by a reaction-sintering process were investigated. Without any calcination, the mixture of PbO, Zn(NO3)2, Fe(NO3)3, Nb2O5 and WO3 for stoichiometric PZNFW and PFNW was pressed and sintered directly. Pyrochlore phase more than 25% were formed in PZNFW ceramics after 2 h sintering at 930–980∘C. PFNW ceramics of 100% perovskite phase were obtained after 4 h sintering at 930–1080∘C. A density of 8.13 g/cm3 (93.4% of theoretical value) was obtained after sintered at 1080∘C for 4 h. Dielectric constant at room temperature under 1 kHz reaches 32000 after sintered at 1080∘C for 4 h.