Sr_xBa_(1-x)Bi_4Ti_4O_(15)陶瓷及SrBi_4Ti_4O_(15)/BaBi_4Ti_4O_(15)复合材料的性能研究  

Preparation and Dielectric Properties of Sr_xBa_(1-x)Bi_4Ti_4O_(15) Ferroelectric Ceramics and SrBi_4Ti_4O_(15)/BaBi_4Ti_4O_(15) Composites

作　　者：黄平[1] 徐廷献[1] 

机构地区：[1]天津大学先进陶瓷与加工技术教育部重点实验室,天津300072

出　　处：《稀有金属材料与工程》2005年第8期1226-1229,共4页Rare Metal Materials and Engineering

基　　金：国家自然科学基金重大资助项(59995520);NipponSheetGlassFoundationforMaterialsScienceandEngineering(Japan)资助项目(301-05544)

摘　　要：采用固相烧结工艺制备了SrxBa1-xBi4Ti4O15铁电陶瓷和SrBi4Ti4O15/BaBi4Ti4O15铁电复合材料。在固相反应过程中,680℃时SrBi4Ti4O15或BaBi4Ti4O15开始生成;800℃时材料主晶相基本形成,但是还有微量焦绿石相存在;850℃时SrBi4Ti4O15或BaBi4Ti4O15的主要衍射峰全部出现。随着Ba含量的增加,SrxBa1-xBi4Ti4O15陶瓷的居里温度逐渐降低。Sr0.5Ba0.5Bi4Ti4O15陶瓷的介电常数峰在高频时较宽,在100Hz时,介电常数峰被随温度升高而逐渐增大的介电常数所“屏蔽”,材料介电损耗随温度升高而增大,但在低频下增加得更快,这是高温下由氧空位引起的电子松弛极化造成的。将预烧后的SrBi4Ti4O15和BaBi4Ti4O15粉体分别造粒后再均匀混合,压片成型,经烧结制得的SrBi4Ti4O15/BaBi4Ti4O15复合陶瓷其相变弥散特性明显优于SrxBa1-xBi4Ti4O15的相变弥散特性。SrxBa1-xBi4Ti4O15 （x=0, 0.15, 0.5, 0.65 and 1.0） bismuth-layered ferroelectric ceramic samples and SrBi4Ti4O15/BaBi4Ti4O15 composites were synthesized by solid-phase reaction process. Two steps heat treatment was used to get dense samples. The first heat treatment was the solid phase reaction and the second step was for the densification. During the solid-state reaction, the formation of SrBi4Ti4O15 and BaBi4Ti4O15 started at 680℃, and the amount of SrBi4Ti4O15 or BaBi4Ti4O15 increased rapidly with a rise in heating temperatures. Nearly all diffraction peaks of SrBi4Ti4O15 or BaBi4Ti4O15 appeared at 800℃, but a small pyrachlore phase still presented. The single phase SrBi4Ti4O15 or BaBi4Ti4O15 was completely formed at 850℃. The curie temperature of SrxBa1-xBi4Ti4O15 ceramics decreases accompanied by peak broadening, with increasing Ba^2＋ level. At high frequency, the dielectric constants of Sr0.5Ba0.5Bi4Ti4O15 samples have a broad peak, whereas at 100 Hz, the broad peak is almost shadowed by a gradual increased dielectric constant with an increasing temperature. The dielectric loss increases with the temperature increases, however, the increase at 1 kHz is significantly faster than that at 10 kHz. This may be related to oxygen vacancy induced polarization. SrBi4Ti4O15/BaBi4Ti4O15 composites were prepared according to the following routes： the fired powders of SrBi4Ti4O15 and BaBi4Ti4O15 were granulated and then admixed with a desired weight ratio and then pressed into pallets and sintered. The dispersion characteristic of phase transition of SrBi4Ti4O15/BaBi4Ti4O15 composites is more apparent than that of SrxBa1-xBi4Ti4O15 ceramics.

关 键 词：SrxBa1-xBi4Ti4O15铁电陶瓷 SrBi4Ti4O15/BaBi4Ti4O15复合材料 介电性能 

分 类 号：TB332[一般工业技术—材料科学与工程]