Piezoelectric ceramic PZT material

When piezoelectric plate crystal is doping concentration of piezoelectric ceramic material Mn is low, Mn mainly enters the crystal lattice, piezoelectric transducer pressure sensor distorts the crystal lattice and promotes the sintering of the piezoelectric ceramic material that leads to the grain growth. However, when the Mn content reaches a certain value, Mn of piezoelectric plate datasheet accumulates at the grain boundaries, pinning the grain boundaries, hindering the growth of the grains and reducing the grain size of the samples. It can also be seen from the cross-sectional secondary electron image of the sample that as the Mn doping amount increases, the strength of the piezoelectric transducer displacement measurement decreases because most of the grains are broken when is breaking the specimen, which may be related to the volume of strength effect, but the more important factor may be Mn doping. Dielectric properties of piezoelectric disc ultrasonic transformer are X and tan W curves for different Mn is doping levels at room temperature. It can be seen from the figure that the incorporation of Mn decreases the X and tan W decreases as the amount of incorporation increases. When the amount of Mn is doping≤0.4%, which is belonging to "hard" additives, Mn enters into the lattice,The samples showed acceptor doping characteristics, so that the dielectric constant of the sample decreased; when the Mn doping r> 0.4%, high frequency piezoelectric crystal enters into the grain boundary, the grain size decreases and the grain distribution is also very uneven, This will also reduce X and tan W. Larger grains reduce the stress on the grain boundaries during polarization and decrease the dielectric loss, which is one of the reasons why tan W decreases with increasing Mn doping. Curie temperature in this experiment is measured by measuring the relative dielectric constant X and temperature T curve to measure the TC, quaternary piezoelectric ceramics Tc and d33 and Mn doping curve. TC's law of change is exactly the opposite.