In this paper, cold sintering was served as a forming method to assist the conventional sintering, which is so-called cold sintering assisted sintering (CSAS) method. Lead-free K_0.5Na_0.5NbO₃ piezoelectric ceramics were prepared by the CSAS method, and the effects of the different procedures on the sintering behaviors and electrical properties of KNN ceramics were studied. Compared with conventional sintering (CS), cold sintering process can induce potassium-rich phase on the KNN particle surface, and remarkably increase both the green and sintering density of KNN ceramics. Meanwhile, the potassium-rich phase would transform to K₄Nb₆O₁₇ second phase on the grain surface, and subsequently suppress the volatilization of potassium element. The sinterability and electrical properties were greatly improved, and KNN piezoelectric ceramics with high performance can be manufactured in a wide sintering temperature range (1055 °C–1145 °C), which proves that CSAS has the potential to be an excellent sintering technique for producing KNN based ceramics.

在本文中，冷烧结被用作辅助传统烧结的成型方法，即所谓的冷烧结辅助烧结（CSAS）方法。采用CSAS方法制备了无铅K _0.5 Na _0.5 NbO ₃压电陶瓷，研究了不同工艺对KNN陶瓷烧结行为和电性能的影响。与常规烧结（CS）相比，冷烧结过程可以在KNN颗粒表面诱导出富钾相，并显着提高KNN陶瓷的生坯和烧结密度。同时，富钾相将转化为K ₄ Nb ₆ O ₁₇第二相在谷物表面，并随后抑制钾元素的挥发。烧结性和电性能得到极大改善，并且可以在较宽的烧结温度范围（1055°C–1145°C）下制造高性能的KNN压电陶瓷，这证明CSAS有望成为一种优异的烧结生产技术基于KNN的陶瓷。