Phase relation and dielectric properties in (Bi1/2 Na1/2)1−x Bax TiO3 TiO3 lead-free ceramics

The diffuse phase transition behavior of the (Bi1/2 Na1/2)1−x Bax TiO3 TiO3 solid solutions were investigated from the ε ( T ) curve. The temperature due to the structural change coincided with the abrupt jump in ε ( T ) curve. The dielectric constant maximum and the dielectric constant minimum were important parameters to define the phase transition. (Bi1/2 Na1/2)1−x Bax TiO3 TiO3 system has the phase transition sequence from rohmbohedral to tetragonal. The phase transition of (Bi1/2 Na1/2)1−x Bax TiO3 TiO3 system was accompanied with structural changes. When x is 0.06, 0.08 and 0.12, (Bi1/2 Na1/2)1−x Bax TiO3 TiO3 showed the diffuse phase transition as a relaxor. Na1/2)1−x Bax TiO3 TiO3 system related to the diffuse phase transition had the antiferroelectric phase. (Bi1/2 Na1/2)0.9 Ba0.1 TiO3 system showed the ferroelectric properties with the remanent polarization of 18  μ C/cm2 and the coercive electric field of 10 kV/cm.