KNN基压电陶瓷材料的制备与性能研究

发布时间：2018-04-19 08:52

本文选题：压电陶瓷 + KNN　；参考：《昆明理工大学》2017年硕士论文

【摘要】：压电陶瓷材料因其独特的性能,被广泛应用于压电陶瓷点火器、压电变压器、压电陶瓷拾音器及扬声器等领域。目前,得到最广泛应用的是铅基压电陶瓷材料,但是铅基压电陶瓷材料在生产和使用的过程中能够生成对人体健康和环境毒害作用的氧化铅,所以很多国家下达了对铅基压电陶瓷材料的使用禁令。所以,开发新型无铅基压电陶瓷材料吸引了各国学者与研究者的目光。本论文中所有样品均采用传统固相烧结法制备,并对它们的压电物性做了系统研究。首先,我们研究了 Sb5+离子对KNN压电陶瓷的物相结构、显微形貌以及其电学性能的影响。XRD与显微形貌分析结果如下:当Sb5+离子掺杂含量在0.02≤x≤0.03范围内时,样品为纯的钙钛矿结构,而当掺杂含量大于0.03时样品中出现了第二相结构;并且Sb5+离子的掺杂可以有效提高KNbO3与NaNbO3之间的固溶度;同时随着Sb5+掺杂含量的增加,样品由正交相转变为四方相结构,当Sb5+离子掺杂含量的进一步增加时,样品开始向伪立方相转变。随着烧结温度的升高样品中晶粒尺寸呈现先减小后增大的现象,说明Sb5+离子在一定程度上具有助烧的效果。当烧结温度为1060℃时,样品晶粒尺寸均匀,排列较紧密,气孔率较低。KNN基陶瓷样品在1060℃下烧结并且Sb5+离子掺杂含量为x=0.02时取得最佳的综合性能d33=98pC/N;Qm2456;kp=0.3229;εr= 1043.963;tanδ=0.7836%。其次,我们通过掺杂第二组元BaTiO3,研究了第二组元BaTiO3对KNN基压电陶瓷的影响。通过XRD和显微形貌分析结果如下:当BaTiO3掺杂含量较少时,样品中出现了第二相结构。而随着掺杂量的增大,BaTiO3与KNN之间形成固溶体的固溶度增大,当x=0.03时样品中第二相消失。并且随着掺杂含量的增加,样品中存在正交-四方两相之间的转变。在1080℃下烧结并且掺杂含量为x=0.02时,样品取得最佳的晶粒分布,晶粒大小较均匀,排列相对紧密,气孔率较低。在1080℃下烧结的0.98KNN-0.02BT的陶瓷样品取得了最佳的综合性能:d33=108pC/N;Qm=852.29;kp=0.3;εr=1421;tanδ=0.528%。在BaTiO3掺杂的基础上我们通过掺杂MnO2对其物相结构、显微形貌以及其电学性能进一步进行调控。结果如下:MnO2在钙钛矿晶体结构中固溶度较小,当MnO2掺杂量过多时样品中出现了杂相。MnO2少量掺杂时Mn4+完全进入晶格,表现为“受主”掺杂的特性;而大量MnO2掺杂时,主要起到烧结助剂的作用。当x=0.01时样品为纯的钙钛矿结构。当MnO2掺杂量在0.01≤x≤0.03范围内并且烧结温度为1080℃时,样品晶界清晰,排列紧密,气孔率较小。在1080℃下烧结并且当掺杂含量为x=0.03时的样品取得最佳的综合性能:d33=159pC/N;Qm=3435;kp=0.2415;εr=701.9;tanδ=0.4068%。最终,我们主要研究了 LiNbO3掺杂对KNN基压电陶瓷物相结构、显微形貌以及其电学性能的影响。分析结果如下:样品掺杂LiNbO3之后出现了第二相的衍射峰,并且随着LiNb03掺杂含量的增加,样品中出现了正交-四方两相之间的转变,并且随着LiNb03掺杂含量的进一步增加,样品中出现了四方相-伪立方相两相之间的转变。随着LiNb03掺杂含量的增加,样品晶粒尺寸逐渐增大,并且当x=0.03时样品晶粒之中出现了气孔等缺陷,并且随着LiNb03掺杂含量的增加样品晶界出现不清晰的现象。当x=0.02时样品取得最优的综合性能:d33=116pC/N;kp=0.326;Qm=2191;εr=699;tanδ=0.324%。
[Abstract]:The piezoelectric ceramic materials because of its unique properties, are widely used in piezoelectric ceramic ignitor, piezoelectric transformer, piezoelectric ceramic microphone and speaker and other fields. At present, is the most widely used lead based piezoelectric ceramic materials, but the lead based piezoelectric ceramic materials in the production and use of the process generation of lead toxicity to human health and the environment, so many countries issued the lead based piezoelectric ceramic materials using the ban. Therefore, the development of new lead-free piezoelectric ceramic based materials have attracted the attention of scholars and research countries. In this thesis the samples by conventional solid phase sintering, and piezoelectric its physical properties were studied. Firstly, we study the Sb5+ ions on the KNN piezoelectric ceramics phase structure, microstructure and electrical properties of.XRD and the influence of microstructure analysis results are as follows: when the Sb5+ ion doped Impurity content in 0.02 = x = 0.03, range, samples are perovskite, while the doping content is more than 0.03 samples appeared in the second phase structure; and the doping of Sb5+ can effectively improve the solid solubility between KNbO3 and NaNbO3; and with the increase of Sb5+ doping content, samples by orthogonal phase transformation for the tetragonal structure, further increases when the Sb5+ doping content, the sample to the pseudo cubic phase transition. With the increase of sintering temperature the grain size in samples showed first decreased and then increased, indicating that Sb5+ ion in a certain extent with the sintering effect. When the sintering temperature is 1060 degrees centigrade, grain uniform size, arranged more closely, the low porosity of.KNN ceramic samples sintered at 1060 DEG C and Sb5+ ion doping content has the best comprehensive performance of d33=98pC/N x=0.02; Qm2456; kp=0.3229; r= tan delta epsilon 1043.963; =0.7836%. then, we doped with second element BaTiO3, the effect of the second component BaTiO3 of KNN based piezoelectric ceramics. Through XRD and microstructure analysis results are as follows: when less BaTiO3 doping content, the second phase structure of the sample. With the increasing of doping amount, solid solubility. Between BaTiO3 and KNN, when x=0.03 of the second phase in the sample and disappear. With the increase of doping content, there is a change of the orthorhombic tetragonal two-phase between samples. Under the temperature of 1080 DEG C sintering and the doping content of x=0.02, the sample has the best distribution of grain, the grain size is uniform, arranged in a relatively close, the porosity is low sintering at a temperature below 1080 DEG 0.98KNN-0.02BT ceramic sample has the best comprehensive performance: d33=108pC/N; Qm=852.29; kp=0.3; e r=1421; tan delta =0.528%. based on BaTiO3 doped we through MnO2 doping on the The phase structure, microstructure and electrical properties of further regulation. The results are as follows: MnO2 in perovskite structure solid solubility is smaller when the doping amount of MnO2 is excessive occurred in the sample phase of.MnO2 when the doping amount is small Mn4+ completely into the lattice, is characteristic of "acceptor" doping; and a large number of MnO2 doping, the main the effects of sintering additives. When x=0.01 samples are perovskite. When the doping amount of MnO2 at x = 0.01 ~ 0.03 range and the sintering temperature is 1080 degrees centigrade, the samples with clear boundaries, closely arranged, the porosity is smaller. Under the temperature of 1080 DEG C and sintering when the doping content of x=0.03 samples obtained the best performance: d33=159pC/N; Qm=3435; kp=0.2415; r=701.9 =0.4068%. tan delta epsilon; finally, we mainly study the LiNbO3 doping of KNN based piezoelectric ceramics phase structure, microstructure and electrical properties of the impact analysis. The results are as follows: the second phase of the diffraction peak appeared after the samples doped with LiNbO3, and with the increase of LiNb03 doping content, changed the orthorhombic tetragonal between the two samples, and with the further increase of LiNb03 doping content, the change of pseudo cubic tetragonal phase between samples. With the increase of LiNb03 doping the content of the sample, the grain size increases, and when x=0.03 samples appear porosity and other defects, and with the increase of the content of LiNb03 doped samples appeared in the grain boundary is not clear phenomenon. The comprehensive performance of samples to obtain the best when x=0.02: d33=116pC/N; kp=0.326; Qm=2191; e r=699; Tan =0.324%..

【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ174.1

【参考文献】