丝网印刷技术制备高性能织构化K_(0.45)Na_(0.55)NbO_3陶瓷(英文)  

Enhanced Ferroelectric and Piezoelectric Properties of Textured K_(0.45)Na_(0.55)NbO_3 Ceramics Prepared by Screen-printing Technique

作　　者：李亚利[1] 惠春[1] 李永祥[2] 王有亮[2] LI Ya-Li;HUI Chun;LI Yong-Xiang;WANG You-Liang(School of Biomedical Engineering,Shanghai Jiao Tong University,Shanghai 200030,China;The Key Laboratory of Inorganic Functional Materials and Devices,Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China)

机构地区：[1]上海交通大学生物医学工程学院,上海200030 [2]中国科学院上海硅酸盐研究所,中国科学院无机功能材料与器件重点实验室,上海200050

出　　处：《无机材料学报》2012年第2期214-218,共5页Journal of Inorganic Materials

基　　金：National Basic Research Program of China(2009CB623305);National Natural Science Foundation of China(50932007)

摘　　要：以片状NaNbO3晶粒为模板,以K4CuNb8O23(KCN)为助烧剂,通过丝网印刷技术制备出晶粒定向的K0.45Na0.55NbO3(KNN)无铅压电陶瓷.片状的NaNbO3模板是以铋层状Bi2.5Na3.5Nb5O18为前驱物,通过熔盐拓扑微观反应制得.织构化(K0.45Na0.55)NbO3陶瓷的晶粒定向程度达到95%,其定向晶粒沿丝网印刷方向平行排列,块体的相对密度达到92%.在平行和垂直于丝网印刷方向的两个面上,织构化(K0.45Na0.55)NbO3陶瓷表现出不同的定向程度,且其介电、铁电和压电性能均明显优于无织构化陶瓷.介电常数εr、压电系数d33、机电耦合系数kp在平行于丝网印刷方向的表面上,分别提高了75%、44%、42%;在垂直于丝网印刷方向的表面上分别提高了35%、30%、35%.相对于目前其它的晶粒定向技术,丝网印刷方法既简单又高效.Grain oriented K0.45Na0.55NbO3（KNN） lead-free piezoceramics with sintering aid K4CuNb8O23（KCN） were fabricated by screen-printing technique,using plate-like NaNbO3 as templates.The plate-like NaNbO3 template particles were synthesized from bismuth layer-structured Bi2.5Na3.5Nb5O18 precursors by the topochemical micro-crystal conversion method.The textured KNN ceramics showed brick-wall-like grains which aligned parallel to the screen-printing direction.The screen-printed KNN ceramics possessed both a high grain orientation（Lotgering factor f=95%） and a relative high density（92% of theoretical density）.The orientation degree and electrical properties of textured（K0.45Na0.55）NbO3 ceramics exhibited anisotropic feature in the parallel（sp//） and perpendicular（sp⊥） plane.Compared with the random oriented ceramics with same composition,the dielectric constant εr,piezoelectric constant d33,and electromechanical coupling coefficient kp were increased by about 75%,44% and 42% in sp// plane,respectively,and about 35%,30% and 35% in sp⊥ plane,respectively.Screen-printing is a simple and effective method for the fabrication of grain oriented lead-free piezoelectric ceramics.

关 键 词：晶粒定向 织构化 丝网印刷 KNN陶瓷 

分 类 号：TB321[一般工业技术—材料科学与工程]