Structure and Dielectric Properties of Pb(Sc(2/3)W(1/3))O(3)-Pb(Zr/Ti)O(3) Relaxors

• Published in: Journal of the American Ceramic Society 2004-11, Vol.87 (11), p.2086
• Main Authors: Juhas, Pavol, Davies, Peter K, Akbas, Mehmet A
• Format: Article
• Language: English
• Subjects: Ceramics; Dielectric properties
• ISSN: 0002-7820; 1551-2916

The structure and dielectric properties of (1-x)Pb(Sc2/3W1/3)O3-(x)Pb(Zr/Ti)O3 ceramics have been investigated over a full substitution range. All compositions with x less than 0.5 adopt a cubic perovskite structure; however, for x less than 0.25 a doubled cell results from a 1:1 ordered distribution of the B-site cations. The structural order in Pb(Sc2/3W1/3)O3 (PSW) can be described by a random-site model with one cation site occupied by Sc3+ and the other by a random distribution of (Sc1/33+W2/36+). The ordering is destabilized in solid solutions of PSW with PbZrO3 (PSW-PZ), but stabilized by PbTiO3 in the (1-x)PSW-(x)PT system. The changes in order are accompanied by alterations in the dielectric response of the two systems. For PSW-PZ the temperature of the permittivity maximum (T epsilon ,max) increases linearly with x; however, for PSW-PT Talt epsilon,maxdecreases in the ordered region (up to x = 0.25) and then increases rapidly as the order is lost. Similar effects were produced by modifying the degree of order of (0.75)PSW-(0.25)PT; when the order parameter was reduced from 1.0 to 0.65, Talt epsilon,max increased by more than 60 degrees C. [PUBLICATION ABSTRACT]