Abstract
The piezoelectric coefficient dh and dielectric coefficients of the PMNT varied with hydrostatic pressure were measured by an airtight chamber filled with the compressed silica oil. The dielectric coefficients varied with vertical pressure also were measured by a vertical pressure system. The results under hydrostatic pressure show that the permittivity increases slowly with the pressure. The relative variety is less than 1.8 % within the pressure of 10 MPa, the dielectric loss has no observable change with the pressure. The piezoelectric coefficients dh and gh have almost no variety from 0 to 10 MPa. The results under vertical pressure show that the permittivity and dielectric loss vary evidently with pressure, the dielectric peaks appear when the pressure increase upper 2 MPa.
Acknowledgment
This work has been supported by the National Natural Science Foundation of china (No.60572004) and Beijing Key Laboratory Open Foundation (No. KM 200810772005).