Phase Diagram and Phase Transitions in the Relaxor Ferroelectric Pb(Fe2/3W1/3)O3–PbTiO3 System

✍ Scribed by L Feng; Z.-G Ye

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 275 KB
• Volume: 163
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2001.9433

✦ Synopsis

A complete solid solution between relaxor ferroelectric Pb(Fe 2/3 W 1/3 )O 3 (PFW) and ferroelectric PbTiO 3 (PT), (1؊x)PFW+xPT, was synthesized by a B-site precursor method and characterized by X-ray di4raction, di4erential scanning calorimetry, and dielectric measurements. A phase diagram between PFW and PT has been established. The di4use phase transition temperature (T max +180 K) of PFW was found to continuously increase with the increasing amount of Ti 4؉ ions on the B-site. At the same time, the relaxor ferroelectric behavior of PFW is gradually transformed toward a normal ferroelectric state, as evidenced by sharp and nondispersive peaks of dielectric permittivity around T C for x50.25. At room temperature, a transition from a cubic to a tetragonal phase takes place with x increased up to 0.25. A morphotropic phase boundary is located within the composition interval 0.254x40.35, which separates a pseudocubic (rhombohedral) phase from a tetragonal phase.

2002 Elsevier Science (USA)