烧结温度对多孔陶瓷压电性能的影响

Effects of Sintering Temperature on Properties of Porous PZT Ceramics

研究了烧结温度对海藻酸钠离子凝胶法制备3-1型多孔PZT压电陶瓷和凝胶注模法制备3-3型多孔PZT压电陶瓷性能的影响。结果表明:当烧结温度从1 150℃升至1 250℃,多孔PZT陶瓷的孔隙率降低,晶粒尺寸、介电常数、压电系数、厚度机电耦合系数和抗压强度增大,静水压压电系数与静水压品质因数随之降低。3-1型PZT陶瓷具有定向直通孔结构,且在成型过程中引入Ca^(2+)。因此,在相同的烧结温度下,3-1型PZT陶瓷的介电常数和抗压强度高于3-3型PZT陶瓷,可靠性和稳定性更强,压电系数和静水压品质因数则低于3-3型PZT陶瓷,灵敏度下降。3-1型PZT陶瓷的静水压品质因数最高可达到4 755×10^(-15)Pa^(-1),适用于高灵敏度压电水听器。

3-1 type and 3-3 type porous PZT ceramics were fabricated by the alginate ionotropic gelation process and gelcasting technology respectively.The resultant samples were sintered at different temperatures and characterized in terms of both microstructure and piezoelectric properties.It was noted that the porosity and grain size of porous PZT ceramics increased with the sintering temperature increasing from 1 150 to 1 250℃,which resulted in the increase of relative permittivity,piezoelectric efficient,thickness coupling coefficient k_(t)and compressive strength,the corresponding decrease of hydrostatic voltage coefficient and hydrostatic figure of merit (HFOM).Under the joint effects of unidirectionally aligned channels and the incorporation of Ca^(2+)into PZT matrix,the 3-1 type PZT ceramics possessed higher ε_(r)and compressive strength,lower d_(33)and HFOM than that of 3-3 type PZT ceramics.However,the maximum HFOM value of 3-1 type PZT ceramics achieved 4 755×10^(-15)Pa^(-1),which makes it suitable for the application of underwater sonar detectors.