Comparative studies on structure, dielectric, strain and energy storage properties of (Bi_(0.5)Na_(0.5))_(0.94)Ba_(0.06)Ti_(0.965)(Mg_(1/3)Nb_(2/3))_(0.035)O_3 lead-free ceramics prepared by traditional and two-step sintering method

摘要

Abstract This work compared the effects of sintering methods on the structure, dielectric, strain and energy storage properties of (Bi~(0.5)Na~(0.5))~(0.94)Ba~(0.06)Ti~(0.965)(Mg~(1/3)Nb~(2/3))~(0.035)O~(3)(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/cm_(3)) 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.