摘要压电陶瓷作为功能材料的典型代表之一,在现代社会的生产生活中起着极其重要的作用。传统的压电陶瓷是以铅为主要成分的锆钛酸铅(PZT),因其具有较好的压电性能而被广泛地应用。然而,锆钛酸铅基压电陶瓷在长期的使用过程中,其内部的铅挥发会对自然环境和人体健康产生危害。多年以来,人们已经研究了多种体系的无铅压电陶瓷并取得了相应的成果。(1-x)BNT-xBKT二元系无铅压电陶瓷作为一种“环境友好型”新型压电材料,近些年来广受人们关注,同时也是本论文所要重点研究的对象。33540
本论文重点介绍了采用水热合成法制备五种不同体系的BNT-BKT粉体. XRD测量显示:不同工艺参数的(1-x)BNT-xBKT均为钙钛矿型结构,说明采用水热法制备粉体的方法可行;当x=0.17时,陶瓷发生结构型相变,说明此时陶瓷体系位于准同型相界附近。SEM图谱表明,当x=0.17时,体系的晶体结构致密度最好。通过测量压电系数d33和机电耦合系数Kp发现,当x=0.17时,陶瓷的压电系数d33达到最大值,为124pC∕N;机电耦合系数Kp也达到最大值,为0.32。分别在 900 ℃、1000℃、1100℃和1200℃四个温度区间对0.83BNT-0.17BKT体系的陶瓷进行烧结,最后测量d33,发现当烧结温度为1100℃时,陶瓷具有最大的压电系数,为121pC∕N。
关键词 BNT-BKT陶瓷,无铅压电陶瓷,压电系数,机电耦合系数
毕业论文设计说明书外文摘要
Title Preparation and characterization of
BNT-BKT lead free piezoelectric ceramics
Abstract
As a typical representative of functional materials, piezoelectric ceramics play an important role in the production and life of modern society. The traditional piezoelectric ceramics are lead zirconium titanate ceramics, which use lead as the main component. The ceramics have good piezoelectric properties and are widely used. However,during the time using lead zirconium titanate based ceramics ,the loss of lead is harmful to the natural environment and human health. Over the years, people have studied the lead-free piezoelectric ceramics of many kinds and achieved the corresponding results. In recent years, (1-x) BNT-xBKT binary system lead-free piezoelectric ceramic, as a kind of environment friendly piezoelectric materials,have greatly attracted people's attentions, and it’s also studied as a main object in this paper. This paper introduces five kinds of different BNT-BKT ceramics prepared by hydrothermal method and the ceramics were tested by XRD measurement. The results showed that all samples possed perovskite structure by different processes, which means it is feasible to prepare the powders by hydrothermal method;At x=0.17, the ceramics undergo structural phase transition,indicating that rhombohedral–tetragonal MPBs exist. The SEM picture shows that the crystal structure of the ceramics comes the best at x=0.17.By measuring the piezoelectric constant d33 and the electromechanical coupling coefficient (KP),the results show that,at x=0.17 piezoelectric constant d33 reached the maximum,which is 124pC∕N and the electromechanical coupling coefficient (KP) reached the most as well.
Keywords BNT-BKT Ceramics ,Lead-free piezoelectric ceramics, Piezoelectric constant ,Electromechanical coupling coefficient.
目 次
1 绪论 1
1.1引言 1
1.2压电陶瓷 1
1.2.1压电陶瓷的应用 1
1.2.2压电陶瓷的发展概况 2
1.3无铅压电陶瓷的推广及使用前景 3
1.3.1压电陶瓷材料的体系 4
1.4钛酸铋钠基(BNT)无铅压电陶瓷的掺杂改性研究 7 BNT-BKT无铅压电陶瓷的制备与表征:http://www.youerw.com/cailiao/lunwen_30699.html