The piezoelectric-enhanced (Na_0.535K_0.475)(Nb_0.55Ta_0.45)O₃ (NKNT) ceramics with Na/K excess and Ta substitution were prepared near the polymorphic phase composition with an orthorhombictetragonal structure. The dielectric, piezoelectric, and ferroelectric properties of the lead-free NKNT ceramics are discussed. The temperature dependences of the specific dielectric and ferroelectric properties were investigated in detail. Broadened dielectric anomalies and saturated ferroelectric P-E hysteresis loops were observed over the phase transitional temperature range of the orthorhombic-tetragonal phase (T^O−T). Additionally, the particular behaviors of the dielectric and the ferroelectric polarizations at the polymorphic phase boundary (PPB) are also discussed.

中文翻译：

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斜方四方多晶相变压电增强（Na 0.535 K 0.475）（Nb 0.55 Ta 0.45）O 3陶瓷的介电响应和铁电极化

在具有正交四方结构的多晶相组成附近，制备了具有Na / K过量和Ta取代的压电增强（Na _0.535 K _0.475）（Nb _0.55 Ta _0.45）O ₃（NKNT）陶瓷。讨论了无铅NKNT陶瓷的介电，压电和铁电性能。详细研究了特定介电和铁电特性的温度依赖性。在正交-四方相的相变温度范围内（T ^O-T）观察到了更大的介电异常和饱和铁电PE磁滞回^线。）。此外，还讨论了在多态相边界（PPB）处电介质和铁电极化的特定行为。