论文总字数：22501字

摘 要

近年来，应用广泛的反铁电材料大多数以锆钛酸铅(PZT)为主。但这些材料大多数含铅，所以在制备的过程中，会给人体和环境造成严重的危害。为了响应可持续发展的号召，减小各领域在材料加工，应用和废弃阶段给环境带来的污染，因此，无铅反铁电陶瓷的研究满足了人类社会的要求。本论文通过对BNT陶瓷掺杂其他组分或元素，改变工艺参数等方面来探索其对陶瓷的物相，微观形貌，反铁电性能的影响。

论文对BNT掺杂一定量的SrTiO₃(ST)，采用传统固相法进行制备二元固溶体BNT-100xST，从而进行反铁电性能研究。实验分两部分进行:第一部分选取烧结温度分别为1120 ℃、1140 ℃、1160 ℃和1180 ℃的四组温度制备BNT-25ST无铅反铁电陶瓷，之后对四种陶瓷样品进行微观性能、P-E回线及S-E曲线分析。发现当烧结温度为1180 ℃时，整个陶瓷体系具有较为均匀的晶体颗粒及较高的相对致密度，最大极化、储能都是最大的(Pmax=48.16 μC/cm²，W=0.833 J/cm³)，同时剩余极化强度和矫顽场较低(Pr=12.53 μC/cm²，Ec=11.38 kV/cm)，收缩率最小(11.72%)，反铁电性能最好。

第二部分研究不同组分ST对(1-x)BNT-xST陶瓷性能影响，其中x=0.15，0.20，0.23，0.25，0.30。当ST含量x=0.23时，整个陶瓷体系具有较为均匀的晶体颗粒及较高的相对致密度，晶粒尺寸约为3 μm。低电场下应变最大，当电场E=45 kV/cm时，最大应变为0.43 %。同时剩余极化强度和矫顽场强也较低(Pr=7.33 μC/cm²，Ec=8.37 kV/cm)，收缩率最大(11.72%)，反铁电性能最好。

关键词: 无铅反铁电陶瓷 BNT-ST 反铁电性能 大应变

Abstract

In recent years, headed by lead zirconate titanate (PZT) - based antiferroelectric ceramics widely used. But most of these materials lead, so in the preparation process, cause serious harm to human body and environment. To achieve the sustainable development of human society, the new ring environment friendly ceramic materials has become an extremely urgent task, reduce various fields in materials processing, application and disposal stages to the environment caused by pollution. Therefore, lead-free antiferroelectric ceramics research meet the requirements of human society. This paper through of BNT ceramics doped with other groups or elements, to change the process parameters to explore the matter of ceramic phase, microstructure , the influence of the antiferroelectric properties.

Select the (Bi_0.5Na_0.5)TiO₃ (BNT) as the research object, the traditional solid-state method were prepared, of BNT doping SrTiO₃ (ST) form a binary solid solution BNT100xST. Through the change process parameters of BNT based ceramics storage performance were studied. The experiment divided into two sub: first part selected sintering temperature were 1120 ℃, 1140 ℃, 1160 ℃ and 1180 ℃ four groups of the temperature of preparation ceramic BNT-25ST, after on four kinds of ceramics samples for microscopic properties of the P-E hysteresis loops and the S-E Curve analysis. It is found that when the sintering temperature of 1180 ℃, the entire ceramic system has more uniform crystal particles and high relative density, maximum polarization, energy storage is the largest (mu the Pmax=48.16 C / cm² for, W=0.833 J / cm³), and the residual polarization and coercive field remained at a lower level (mu the Pr=12.53 C/cm² for, Ec=11.38 kV / cm), minimum (11.72 %). Anti ferroelectric properties best shrinkage.

The second part as research emphasis, different research groups points of ST on the (1-x) BNT-xST ceramic performance impact, which x=0.15,0.20,0.23,0.25,0.30. when the ST content was 0.23, the entire ceramic system has more uniform crystal particles and high relative density, average grain size was about 3 m. The low electric field under the maximum strain, when the electric field E=45 kV / cm, the maximum strain for 0.43 % and remanent polarization and coercive field strength is maintained at low levels (Pr=7.33 μC/cm², Ec=8.37 kV/cm), the maximum shrinkage rate (11.72 %).

Key words: lead-free antiferroelectric ceramics; BNT-ST; antiferroelectric properties; strain

目 录

摘要 Ⅰ

Abstract Ⅱ

第一章 绪论 1

1.1引言 1

1.2铁电材料 1

1.2.1铁电体的概念 1

1.2.2典型铁电体的电滞回线 1

1.2.3铁电相变的概念 2

1.3反铁电材料 2

1.3.1反铁电体的概念 2

1.3.2反铁电体的电滞回线 2

1.4反铁电材料的应用 2

1.4.1反铁电储能器 2

1.4.2反铁电爆电换能 3

1.5无铅反铁电陶瓷 3

1.5.1无铅反铁电陶瓷的发展历史 3

1.5.2 近几年来Bi_0.5Na_0.5TiO₃(BNT)基陶瓷的研究成果 3

1.6 本研究课题的提出以及研究内容 5

1.6.1 课题的提出 5

1.6.2研究内容 5

第二章 实验方法与性能表征 6

2.1 实验原料 6

2.2 实验仪器 6

2.3 陶瓷样品的制备工艺： 6

2.4 实验过程： 7

2.5 测试与表征方法 8

第三章 实验内容与分析 10

3.1加入SrTiO₃对BNT基反铁电陶瓷的研究 10

3.2不同烧结温度制备BNT-25ST陶瓷及性能研究 10

3.2.1实验内容 10

3.2.2 不同烧结温度对BNT-25ST陶瓷微观形貌的影响 10

3.2.3 不同烧结温度对BNT-25ST陶瓷P-E回线的影响 11

3.2.4不同烧结温度对BNT-25ST陶瓷S-E曲线的影响 12

3.3不同组分下BNT-ST陶瓷制备及性能研究 13

3.3.1实验内容 13

3.3.2不同SrTiO₃掺杂量对BNT100xST陶瓷物相的影响 13

3.3.3不同SrTiO₃掺杂量对BNT100xST陶瓷微观形貌的影响 14

3.3.4不同SrTiO₃掺杂量对BNT100xST陶瓷电性能的影响 15

3.3.5不同SrTiO₃掺杂量对BNT100xST陶瓷S-E曲线的影响 17

3.4本章小结 18

第四章 结论与展望 19

4.1 结论 19

4.2 展望 19

参考文献 20

致谢 23

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