基于高温压电传感器用铌酸铋钙压电陶瓷的高温导电机制、温度稳定性及抗冲击性能研究

Bismuth layer-structured piezoelectric ceramics are characterized by high Curie temperature, which can be acted as the key components in high-temperature piezoelectric sensors in many fields, such as energy sources, aeronautics and astronautics, metallurgy and chemical industries. However, the piezoelectric properties of these series ceramics are very poor. Moreover, the conductivity increases sharply at high temperature, resulting in poor thermal stabilities, and then limiting their applications at high temperature. Up to now, there is still lack of systematical investigations of their conduction mechanisms and anti-shock properties. Recently, the high performance calcium bismuth niobate piezoelectric ceramics were successfully obtained. In this proposal, the piezoelectric properties of calcium bismuth niobate will be optimized by ions substitutions, different sintering approaches, oxygen atmosphere sintering. The conduction mechanisms will be deeply analyzed by investigating the effects of oxygen vacancies and bismuth ions vacancies in (Bi2O2)2+ layer, and oxygen atmosphere sintering on the conductivity. The aim of this proposal is to obtain high piezoelectric activities calcium bismuth niobate piezoelectric ceramics and piezoelectric sensors, which can work well up to 500℃. The achievements in this proposal are helpful to understand the conduction mechanisms of bismuth layer-structured piezoelectric materials, and promote the development of novel bismuth layer-structured piezoelectric materials and related devices.

压电加速度传感器广泛应用于航空航天、能源、建筑、汽车等行业的振动与冲击测量。铋层状结构材料具有高的居里温度，可用作高温压电传感器的核心元件。但是该类材料高温时电导率增加，导致性能稳定性下降，工作温度范围受到限制。而且荷载的长期效应、疲劳效应导致该类材料的抗冲击性能较差，严重影响压电传感器的准确监控或测量，以及器件的正常使用和服役寿命。目前国内外对其高温导电机理、原位压电性能温度稳定性以及抗冲击性能尚缺乏系统的研究。本申请拟以高居里温度铌酸铋钙为出发点，优化其压电性能的高温稳定性；研究铋层中氧空位、铋离子缺位及气氛烧结对其高温导电性能、压电性能的高温稳定性以及抗冲击性能的影响，揭示导电机理，降低高温电导率，提高压电性能的温度稳定性和抗冲击性能，最终获得可在500℃以上稳定工作的高温压电材料和传感元器件。本项目有助于深刻了解该类材料的导电机理，促进实用高温压电材料和压电传感器件的研制。

压电加速度传感器广泛应用于航空航天、能源、建筑、汽车等行业的振动与冲击测量。铋层状结构材料具有高的居里温度，可用作高温压电传感器的核心元件。但是该类材料高温时电导率增加，导致性能稳定性下降，工作温度范围受到限制。而且荷载的长期效应、疲劳效应导致该类材料的抗冲击性能较差，严重影响压电传感器的准确监控或测量，以及器件的正常使用和服役寿命。目前国内外对其高温导电机理、原位压电性能温度稳定性以及抗冲击性能尚缺乏系统的研究。本申请拟以高居里温度铌酸铋钙为出发点，优化其压电性能的高温稳定性；研究铋层中氧空位、铋离子缺位及气氛烧结对其高温导电性能、压电性能的高温稳定性以及抗冲击性能的影响，揭示导电机理，降低高温电导率，提高压电性能的温度稳定性和抗冲击性能，最终获得可在500℃以上稳定工作的高温压电材料和传感元器件。本项目有助于深刻了解该类材料的导电机理，促进实用高温压电材料和压电传感器件的研制。