Microstructure and properties of Ga-modified 0.7BiFeO3-0.3BaTiO3 solid solution

Binary solid solutions 0.7Bi (GaxFe1-x)O3-0.3BaTiO3 (x = 0, 0.025, 0.05, 0.1) ceramics were prepared by traditional ceramic process. All the ceramic samples showed single perovskite phase except the sam- ple with x = 0.1. The effects of gallium doping on microstructure, ferromagnetic, ferroelectric, dielectric properties and conductivity were investigated. The results indicated that Ga-dopant could improve the sintering ability of the solid solution when the Ga content x was below 0.05. When x was over 0.05, the sintering ability of the solid solution was weakened, and the phase structure of 0.7BiFeO3-0.3BaTiO3 solid solution changed from rhombohedral phase into tetragonal ferroelectric phase. The electrical resistivity increased with the Ga content increasing. Both ferroelectricity and ferromagnetism were observed in all the ceramic samples. With the Ga content increasing, the remanent magnetization Mr increased and the magnetic coercive field Hc decreased. However, the remanent polarization Pr fluctu- ated, increasing firstly and decreasing later.