piezoelectric properties of lead niobate ceramics

In order to improve the sintering piezoelectric properties of lead niobate ceramics,piezoceramic vibration sensor needs to be doped and modified. In general, the commonly used modification is to use M + or M2 + instead of lead, the most of which is Ba2 +. With the increasing of the content of the dopant, the technological performance of the piezoceramic crystal datasheet is improved and the piezoelectric property is also greatly improved, but it affects the Curie temperature, the quality factor and the anisotropy. Curie temperatures, in particular, have dropped dramatically, losing the possibility of their use at high temperatures. It has been found that the lead-modified high-temperature piezoelectric ceramics of niobate lead can be obtained by a small amount of M2 + substitution and trace rare earth element doping, electronic piezoceramic crystal has both high Curie temperature and good piezoelectric properties. The effects of additives and process parameters on the properties of modified lead niobate ceramics and the aging problems were systematically studied.It has recently been reported that doping with Ti and holding at 1 300℃ for 1 h can not only greatly increase the density of 95% the lead niobate sintered ultrasonic piezo disc quartz, but also increase the Curie temperature so that it can be applied to high temperature ultrasonic sensors. In addition to doping modification, other studies piezoelectric transducer car parking sensors hope to improve the performance of the lead niobate lead ceramic by improving the process. Prepared by sol-gel method powder, and then use two-stage heat treatment can be relatively dense lead partial niobate ceramics. A grain-oriented lead meta-niobate ceramic is having a texture of 89% that was prepared using a layered manufacturing method. Compared with the common lead niobate ceramics, the piezoelectric properties of the oriented electrical model piezo have been greatly improved, the piezoelectric coefficient is increased by 30%, while the residual polarization increased by nearly 1 times. In addition to lead niobate lead, the composite tungsten bronze structure of piezoelectric ceramics, such as: Pb4Na2Nb10O30 and Ba4-2xAg2 + xLaxNb10O30 also have a high curie temperature. However, due to the difficulty of sintering and the piezoelectric coefficient is too low, its application has been greatly limited.