In this work, we revisit the phase transition sequence and the effect of the sintering process on the structural, dielectric and polar properties of K_0.5Na_0.5NbO₃ ceramics prepared by conventional sintering, spark plasma sintering and spark plasma texturing. Herein, comparative experimental study of the lattice dynamics, polar and dielectric properties is presented. We observe that the phase transition sequence includes an unreported structural and polar phase at low temperatures, independently on the processing method. Contrarily, we observe apparent changes of the stability temperature interval of the different phases. The dielectric strength and the emergence of a dielectric relaxation phenomenon are also noticeably dependent on the processing method, which can be understood as an effect of the different grain size. The results here reported clearly show the possibility to change physical properties following different sintering routes in order to improve device performance.

在这项工作中，我们将回顾相变顺序以及烧结过程对K _0.5 Na _0.5 NbO ₃的结构，介电和极性性质的影响通过常规烧结，火花等离子烧结和火花等离子变形制备的陶瓷。在此，对晶格动力学，极性和介电性能进行了对比实验研究。我们观察到，独立于加工方法，相变序列包括在低温下未报告的结构相和极性相。相反，我们观察到了不同相的稳定温度区间的明显变化。介电强度和介电弛豫现象的出现也明显取决于加工方法，这可以理解为不同晶粒尺寸的影响。此处报告的结果清楚地表明，按照不同的烧结路线改变物理性质的可能性，以提高器件性能。