使用0-3型PZT/P(VDF-TFE)压电复合材料研制出一种圆柱形水听器,对水听器的结构、材料以及灵敏度进行了理论分析,测量了水听器样品灵敏度随频率的变化曲线。研究结果表明,利用0-3型PZT/P(VDF-TFE)压电复合材料可制作出灵敏度高达-202.3 d...使用0-3型PZT/P(VDF-TFE)压电复合材料研制出一种圆柱形水听器,对水听器的结构、材料以及灵敏度进行了理论分析,测量了水听器样品灵敏度随频率的变化曲线。研究结果表明,利用0-3型PZT/P(VDF-TFE)压电复合材料可制作出灵敏度高达-202.3 dB ref.1V/μPa的水听器,静态电容量较大,制作工艺简单,实际测量值和理论计算值很相近。展开更多
Polyvinylidene fluoride(PVDF)-based copolymers with tetrafluoroethylene(P(VDF-TFE)),trifluoroethylene(P(VDF-TrFE))or hexafluoropropylene(P(VDF-HFP))are of strong interest due to the underlying fundamental mechanisms a...Polyvinylidene fluoride(PVDF)-based copolymers with tetrafluoroethylene(P(VDF-TFE)),trifluoroethylene(P(VDF-TrFE))or hexafluoropropylene(P(VDF-HFP))are of strong interest due to the underlying fundamental mechanisms and the potential ferro-,pyro-and piezo-electrical applications.Their flexibility and their adaptability to various shapes are advantageous in comparison to inorganic ferroelectrics.Here,we study the influence of stretching temperature on the crystalline phases and the dielectric prop-erties in P(VDF-TFE)films by means of Dielectric Relaxation Spectroscopy(DRS),Fourier-Transform InfraRed spectroscopy(FTIR),Wide-Angle X-ray Diffraction(WAXD),Differential Scanning Calorimetry(DSC)and Dynamic Mechanical Analysis(DMA).Especially,the effect of stretching and the influence of the temperature of stretching on the mid-temperature(T_(mid))transi-tion are studied in detail.The results show that stretching has a similar effect as that on PVDF,and we observe an increase in the fraction of ferroelectric b-phase with a simultaneous increment in both melting point(T_(m))and crystallinity(X_(c))of the copolymer.While an increase in the stretching temperature does not have a profound impact on the amount of ferroelectric phase,the stability of the ferroelectric phase seems to improve-as seen in the reduction of the Full Width at Half Maximum(FWHM)of the WAXD peaks in both parallel and perpendicular directions to the molecular chain axis.The observation is also supported by the reduction of dissipation losses with an increase in stretching temperature-as seen in DRS measurements.Finally,both stretching itself and the temperature of stretching affect the various molecular processes taking place in the temperature range of the T_(mid) transition.展开更多
文摘使用0-3型PZT/P(VDF-TFE)压电复合材料研制出一种圆柱形水听器,对水听器的结构、材料以及灵敏度进行了理论分析,测量了水听器样品灵敏度随频率的变化曲线。研究结果表明,利用0-3型PZT/P(VDF-TFE)压电复合材料可制作出灵敏度高达-202.3 dB ref.1V/μPa的水听器,静态电容量较大,制作工艺简单,实际测量值和理论计算值很相近。
文摘Polyvinylidene fluoride(PVDF)-based copolymers with tetrafluoroethylene(P(VDF-TFE)),trifluoroethylene(P(VDF-TrFE))or hexafluoropropylene(P(VDF-HFP))are of strong interest due to the underlying fundamental mechanisms and the potential ferro-,pyro-and piezo-electrical applications.Their flexibility and their adaptability to various shapes are advantageous in comparison to inorganic ferroelectrics.Here,we study the influence of stretching temperature on the crystalline phases and the dielectric prop-erties in P(VDF-TFE)films by means of Dielectric Relaxation Spectroscopy(DRS),Fourier-Transform InfraRed spectroscopy(FTIR),Wide-Angle X-ray Diffraction(WAXD),Differential Scanning Calorimetry(DSC)and Dynamic Mechanical Analysis(DMA).Especially,the effect of stretching and the influence of the temperature of stretching on the mid-temperature(T_(mid))transi-tion are studied in detail.The results show that stretching has a similar effect as that on PVDF,and we observe an increase in the fraction of ferroelectric b-phase with a simultaneous increment in both melting point(T_(m))and crystallinity(X_(c))of the copolymer.While an increase in the stretching temperature does not have a profound impact on the amount of ferroelectric phase,the stability of the ferroelectric phase seems to improve-as seen in the reduction of the Full Width at Half Maximum(FWHM)of the WAXD peaks in both parallel and perpendicular directions to the molecular chain axis.The observation is also supported by the reduction of dissipation losses with an increase in stretching temperature-as seen in DRS measurements.Finally,both stretching itself and the temperature of stretching affect the various molecular processes taking place in the temperature range of the T_(mid) transition.
