Comparative studies on structure, dielectric, strain and energy storage properties of (Bi0.5Na0.5)0.94Ba0.06Ti0.965(Mg1/3Nb2/3)0.035O3 lead-free ceramics prepared by traditional and two-step sintering method

This work compared the effects of sintering methods on the structure, dielectric, strain and energy storage properties of (Bi0.5Na0.5)0.94Ba0.06Ti0.965(Mg1/3Nb2/3)0.035O3 (BNBT–0.035MN) lead-free ceramics. The single phase perovskite structure of BNBT–0.035MN ceramics was independent with sintering methods. The ceramics by two-step sintering had smaller grain size and denser microstructure than those of the ceramics by traditional sintering. Compared with traditional sintering, the ceramics by two-step sintering exhibited better energy storage properties. The optimum energy storage density (W = 0.80 J/cm3) and corresponding efficiency (η = 65%) were obtained at 70 kV/cm, while the electric field-induced strain decreased. Dielectric properties of two-step sintering samples were inferior to that of traditional samples, which is related to the grain size effect.