摘要
采用化学共沉淀法制备了一系列(Sr1-xPbx)TiO3陶瓷粉体,通过差热-热重(DTA-TG)分析确定了共沉淀产物的煅烧温度.X射线衍射(XRD)分析表明,化学共沉淀产物基本上呈非晶态,随后煅烧过程中发生晶化,主晶相为立方(Sr1-xPbx)TiO3固溶体.随着Pb含量的增加,逐渐出现游离的四方PbTiO3次晶相.所制得的(Sr1-xPbx)TiO3粉体具有纳米晶粒及纳米颗粒结构,平均晶粒及颗粒尺寸分别为20-30nm和20-50nm;颗粒形貌为不规则球形,团聚较为严重,以一次团聚颗粒为主,平均直径为200nm,较大的二次团聚体平均粒径约为750nm.纳米粉体烧结成瓷的温度显著降低,在1150℃烧结基本实现致密化,而且由烧结前的立方相为主完全转变为四方相,没有了游离的PbTiO3并存在铁电畴亚结构.
A series of (Sr1-xPbx) TiO3 ceramic powders were prepared through chemical coprecipitation process. The calcining temperature of coprecipitation products was analyzed and determined according to differential thermal and thermogravimetric analysis ( DTA-TG). X-ray diffractometry ( XRD) results showed that, the coprecipitation products are nearly in amorphous state, which crystallized during calcining. The major phase is cubic (Sr1-xPbx) TiO3 solid solution, and the minor phase, tetragonal PbTiO3, extricates from the solid solution with increasing Pb content. The calcined (Sr1-xPbx) TiO3 powders exhibit nanometer crystal grains and nanometer particles whose mean sizes are 20-30 nm and 20-50 nm, respectively. The particles exist in irregular global shape and in agglomerated state. The major agglomerated particles' mean size is 200 nm, and the minor ones' mean size is 750 nm. The sintering temperature decreases obviously, and at 1 150 ℃ the ceramics is nearly densified. The crystal structure of sintered ceramics has changed from cubic to tetragonal, and no extricated PbTiO3but ferroelectric domains exist in sintered ceramics.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2005年第1期108-112,共5页
Materials Science and Technology
