Investigating the Effects of the Mno Additives and Process Conditions on the Relaxor Ferroelectric Ceramics: by Using the Diffuse Phase Transition ... Theory on Pb (Fe2/3w1/3)o3-pbtio3 System

In this thesis, we discuss the low field dielectric behavior by using the diffuse phase transition model, the Curie-Weiss law, the order-disorder model, the Arrehenius law, the Debye theory, the superparaelectric model, the spin-glass model and the modified Landau theory on the PFW-PT based ceramic systems. The X-ray diffractive method and the SEM image are also used to examine the lattice structure and the micro structure in all samples. The effects of the sintering temperature, the MnO additives and the synthesized method are investigated at the same time. Furthermore, the fitting degree and the physical and mathematical means of the diffuse phase transition model are derived by using the statistic theory.