Dielectric properties of solid solutions (1-x)Pb (Sc1/2Ta1/2)O-3-xPbZrO(3)(0 < x < 1)

Dielectric properties of (1 - x)Pb(Sc1/2Ta1/2)O-3(PST)-xPbZrO(3) (PZ) (0 < x < 1) were investigated. For PZ concentrations x < 0.7, a diffuse phase tr ansition was observed. With increasing x, the maximum permittivity epsilon( rm)' increased, and the temperature T-m at which epsilon(rm)' appeared shif ted towards the higher temperature region. For x > 0.7, the permittivity ep silon(r)' exhibits a peak at the phase transition temperature T-c. With inc reasing x, the peak value decreased and T-t shifted towards the higher temp erature region. The phase below T-c was confirmed to be ferroelectric by ob servation of P-E hysteresis loops. Phase transformation from the relaxer to the ferroelectric state occurred at x = 0.7. For x > 0.8, a steplike anoma ly appeared at T-t below T-c. With increasing x, T-t shifted towards the hi gher temperature region. There was a structural change characterized by the splitting of the structure-sensitive maximum of the (200) reflection of XR D patterns, similar to orthorhombic PZ, around x = 0.8. Two morphotropic ph ase boundaries were found: one between the pseudocubic and rhombohedral pha ses with epsilon(rm)' of 15000 at 100 kHz was at x = 0.7, and the other bet ween the rhombohedral and orthorhombic phases was at x = 0.8.