B位掺杂对改性PbTiO_3陶瓷性能的影响

The influences of B-site substitutions to the properties of modified PbTiO_3 ceramics

针对具有大各向异性的钙改性PbTiO3陶瓷材料 ,研究了在B位用镍铌和锌钨联合取代部分钛对材料性能的影响 .研究结果表明 :当Pb(Zn1 2 W1 2 )O3和Pb(Ni1 3Nb2 3)O3的掺杂量为 3 % (mol mol)时 ,样品同时具有较大的压电各向异性和较高的机械品质因素 .分析指出合适的B位取代会引起一定的晶格畸变以及较少的晶格缺位 ,使材料在极化后电畴充分转向 ,有利于提高压电各向异性和机械品质因素 .用XRD和SEM对陶瓷的微观结构进行研究 ,发现随着镍铌取代量的增加 ,晶体结构的四方度有减小的趋势 ,从而导致材料性能相应的变化 。

The relationship of the properties of modified PbTiO 3 ceramics with some B-site substitutions were investigated. The results showed that when the titanate was partially substituted by 3% (mol/mol) of nickel-niobium and 3%(mol/mol) of zinc-tungsten, the samples not only had larger piezoelectric anisotropy but also higher mechanical quality factors. It pointed out that different ions substituted in B-site might cause some crystal lattice deformed and might not cause so many crystal lattice defaults, with these conclusions, the electric-domains could be rerotated sufficiently and at same time the micro-cracks would be reduced less then usual, these can explain why the piezoelectric anisotropy and the mechanical quality factors kept in higher value in the ceramics. By the study of the ceramic's microstructures, it was found that the tetragonal distortions ( c/a ) reduced gradually with the increase of B-site substitutions, this reduce made the properties of the material changed accordingly, such changes can be utilized to adjust the properties of the material appropriately.