成型压力对0-3型锆钛酸铅/水泥压电复合材料的影响

Effects of forming pressure on 0-3 PZT/cement piezoelectric composites

以快硬硫铝酸盐水泥为基体,以锆钛酸铅(PZT)为功能相,用压制成型法制备出0-3型PZT/水泥基压电复合材料。分析成型压力对PZT/水泥基压电复合材料的压电性和介电性的影响,结果表明:不同粒径PZT颗粒作为功能相的水泥基压电复合材料,成型压力对其压电性和介电性有不同的影响。在30~90 MPa压力范围内,成型压力越大,PZT/水泥压电复合材料的压电应变常数d33和相对介电常数εr均显著提高,这是由于气孔率随压力增大而减少,而压电电压常数g33的变化则与功能相的粒径有关。机电耦合系数也有着不同的变化趋势,对于6μm和126μm PZT/水泥压电复合材料,其机电耦合系数Kt和Kp随压力增大缓慢下降,而对于430μm PZT/水泥压电复合材料则呈上升趋势。当压力达到150 MPa时,其压电性和介电性均急剧减小。

0-3 cement-based piezoelectric composites were fabricated by compressing technique, with sulphoalumihate cement as the matrix, Pb（Zr0.52 Ti0.48 ）O3 （PZT）/ceramic as the functional phase. The effects of forming pressure on the cement-based composites of different size PZT particles were investigated. The results indicate that the change in forming pressure affect the piezoelectric and dielectric properties of PZT/cement composites of different size PZT in different ways. In the forming pressure range from 30 MPa to 90 MPa, the piezoelectric strain factors （d33） and the relative dielectric constants （εr） of PZT/cement composites rapidly increase as forming pressure adds due to the reduction of porosity with pressure. However, the change in piezoelectric voltage factors （ga3） with pres- sure is related to the size of PZT. The electromechanical coupling coefficients （K, and Kp） of PZT/cement compos- ites of different sized PZT particles also have distinct changes with forming pressure. For PZT/cement composites of 6 μm or 126 μm size PZT particles, the Kt and Kp reduce with the increasing of forming pressure, while that of composites of 430 μm size PZT particles goes up as forming pressure rises. In addition, both dielectric and piezoelectric performance degrade significantly when forming pressure is up to 150 MPa.