前驱粉粒径对(Pb_(0.945)Bi_(0.027)La_(0.01))(Nb_(0.95)Ti_(0.0625))_2O_6压电陶瓷结构和电学性能的影响

Effect of particle size of precursor powders on structure and electrical properties of (Pb_(0.945)Bi_(0.027)La_(0.01))(Nb_(0.95)Ti_(0.0625))_2O_6 piezoelectric ceramics

在固相法制备陶瓷试样的过程中分别采用高能振动球磨法（I类试样）和普通行星式球磨法（II类试样）制备得到具有不同平均粒径的前驱粉体,研究了前驱粉体粒度对该陶瓷的预烧性能、烧结性能、相结构、显微结构、介电和压电性能的影响。高能振动球磨法获得的前驱粉体在725℃预烧即可得到纯三方相,而采用普通行星式球磨法获得的前驱粉体在900℃预烧才能得到纯三方相。Ⅰ类试样获得纯正交铁电相的烧结温度为1 170-1 185℃,而Ⅱ类试样获得纯正交铁电相的烧结温度为1 180-1 190℃。Ⅰ类试样的晶粒各向异性显著降低。两类陶瓷的介电性能差异并不显著,在室温至400℃温度范围内陶瓷的介电常数均没有明显改变。在1 180℃烧结的Ⅱ类陶瓷试样具有较大的压电常数（d33=87pC/N）,而Ⅰ类陶瓷试样的压电常数略低。

In order to study the influence of the particle size of precursor powders on the dielectric and piezoelectric properties of the（Pb0.945Bi0.027La0.01）（Nb0.95Ti0.0625）2O6piezoelectric ceramics,precursor powders with different average particle size were obtained by means of high-energy vibration milling（sample Ⅰ）and normal planetary milling（sample Ⅱ）.Effects of the particle size of precursor powders on calcination,sintering,phase structure,microstructure,dielectric and piezoelectric properties of the ceramics were studied in detail.The precursor powders prepared via the high-energy vibration milling show the pure rhombohedral phase after calcining at 725 ℃,while the calcination temperature increases to 900 ℃to obtain the pure rhombohedral phase for the precursor powders prepared via the normal planetary milling.Sample I sintered at temperatures from 1 170 to 1 185 ℃ have the single orthorhombic phase,while the sintering temperatures increase to 1 180~1 190 ℃to obtain the single orthorhombic phase for sampleⅡ.The anisotropy of the grains in sample I was weakened obviously.The dielectric properties of the both samples were similar.The values of dielectric constant remain almost unchanged attemperatures between room temperature and about 400℃.SampleⅡsintered at 1 180℃shows improved piezoelectric charge constant（d33=87pC/N）,while sampleⅠ shows a lower d33.