锆锡钛酸铅钡镧反铁电陶瓷储能性能研究

发布时间：2018-09-14 20:57

【摘要】：反铁电体因具有独特的电滞回线以及相转变特征,可被用于高储能密度脉冲电容器中。本文研究的是锆锡钛酸铅钡镧(PBLZST)反铁电陶瓷,该体系的陶瓷具有优异的储能性能。目前有诸多手段可用来提高反铁电陶瓷的储能密度,例如组分调控、元素掺杂、成分复合等,然而新的陶瓷烧结工艺对储能性能的影响,则尚未得到深入研究。因此,本文采用了热压的新工艺,从以下几个方面研究了PBLZST的储能性能:首先,本文对热压烧结工艺进行了设计,分别研究了烧结温度、保温时长、热压压力等因素对反铁电陶瓷性能的影响。实验结果表明:热压烧结制备的PBLZST,其烧结温度比起普通烧结可降低近200℃,可在1100℃下烧结成瓷。同时,保温时间为2小时,热压压力调整到70MP时,陶瓷成瓷效果良好。其次,对于铅基陶瓷体系,烧结过程始终伴随着铅挥发。本文设计了五组不同铅过量组分,研究了PbO过量量对热压和普通烧结的PBLZST微观结构和储能性能的影响。结果表明:通过SEM分析,热压陶瓷样品晶粒轮廓清晰,微结构更加均匀,气孔率低,其中PbO过量量为6mol%的热压样品平均晶粒尺寸为1.8μm,致密度达到99.5%;击穿场强Weibull分析表明热压样品击穿场强普遍较高,最高达到180KV/cm;高压电阻率测试结果表明热压样品电阻率大于1013Ωm,较普通烧结样品高两个数量级;热压法制备的反铁电陶瓷样品,其最高储能密度达到3.2 J/cm3,该储能密度是普通烧结样品的2倍。由于在热压烧结过程中,样品通常处于缺氧状态,烧结的陶瓷会产生氧缺陷,这影响了陶瓷的电性能。本文通过设计不同的氧化后处理工艺,研究了后期氧处理对PBLZST储能性能的影响。结果表明:在850℃下,PBLZST在空气中氧化3小时,或在氧气氛下氧化1.5小时(通氧速率为50 mL/min),氧化效果较好。处理后的PBLZST样品的储能密度得到进一步提高,达到3.45J/cm3。
[Abstract]:Because of its unique hysteresis loop and phase transition, antiferroelectrics can be used in high energy storage density pulse capacitors. The antiferroelectric ceramics of lead barium zirconium tin titanate lanthanum titanate (PBLZST) are studied in this paper. The ceramics of this system have excellent energy storage properties. At present, there are many ways to improve the energy storage density of antiferroelectric ceramics, such as component control, element doping, composition composite, etc. However, the effect of new sintering process on the energy storage performance has not been further studied. Therefore, the new technology of hot pressing is adopted in this paper, and the energy storage performance of PBLZST is studied from the following aspects: firstly, the hot pressing sintering process is designed, and the sintering temperature and holding time are studied, respectively. The effect of hot pressing pressure on the properties of antiferroelectric ceramics. The experimental results show that the sintering temperature of PBLZST, prepared by hot pressing sintering is about 200 鈩，

本文编号：2243845