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Abstract

Lead-free bismuth sodium zirconate (BNZ) ceramics with formula Na 0.5 Bi 0.5 ZrO 3 /xBi 2 O 3 with x = 0, 2, 3, 4, and 6 wt% were prepared by liquid-phase sintering method. The specimens were sintered at 850 and 900°C. Phase identification was investigated using X-ray diffraction technique. BNZ/4 wt% Bi 2 O 3 and BNZ/6 wt% Bi 2 O 3 ceramics sintered at 900°C showed impurity phase of Bi 7.38 Zr 0.62 O 12.31 compound due to excess additive reacted with zirconium in system. Scanning electron microscopy and energy-dispersive X-ray spectroscopy were employed to study microstructure and measure chemical composition of ceramics, respectively. The results revealed creation of bismuth oxide liquid phase at BNZ grain boundaries inhibited grain growth and decreased pore size. This caused the relative densities of the modified samples to increase.

Effects of processing parameter on energy storage density and ferroelectric properties of lead-free bismuth sodium titanate-strontium bismuth titanate ceramics

“…In the present study, we selected the BNT with excellent piezoelectric as base material, and a small amount of SBT was added as additive at the composition of 0.7BNT-0.3SBT ceramics (which showed interesting electrical properties, i.e the W ) [4,10]. Moreover, as sintering process is important for fabrication of ceramic materials [14], the effects of sintering temperatures on the densification, phase, microstructure, dielectric, ferroelectric, and W were investigated and discussed in details. It was expected that the optimum sintering condition could produce ceramics with better properties.…”

Structure and properties of (Na0.5Bi0.5)ZrO3 (NBZ) lead-free perovskite compound

“…A broad ferroelectric-paraelectric phase transition (diffuse phase transition) was reported at 425°C (698 K) [13]. The elaboration of NBZ powders and the densification mechanism of ceramics were studied and the orthorhombic space group Pnma (SG #62) was attributed to NBZ without any structural study [15,16]. Ferroelectric properties were reported for NBZ [17], but: (i) this property is conflicting with the centrosymmetric Pnma space group and (ii) the elliptic shape of hysteresis loop is typical of a lossy dielectric and not of a ferroelectric material [18].…”