| 摘要 |
PURPOSE:To obtain a ferroelectric body with electric field characteristics and durability which can withstand a high voltage and temperature characteristics by using a tetragonal system as a crystalline system and then setting Zr ratio which is expressed by Zr/(Zr+Ti) to an amount which is smaller than the Zr ratio of a phase boundary by a specified amount. CONSTITUTION:A Zr ratio which is expressed by Zr (Zr+Ti) of a ferroelectric body of Pb (Mg1/3Nb2/3)O3-PbZrO3-PbTiO3 system, or Pb (Mg1/3Nb2/3)O3- PbZrO3-PbZrO3-PbTiO3 where a small amount of Bi2O3, SnO2, ZnO, and StO are added, and a tetragonal system is set to an amount which is at least 0.5mol% smaller than the Zr ratio at a phase boundary. The Figure shows a plotted piezoelectric d constant which is calculated based on a distortion in 31 directions which is generated in this case by applying a DC voltage to this ferroelectric body. It is desirable to use a sample which is in tetragonal system, has a Zr ratio of approximately 38.5 for obtaining the d constant which is proportional to a strength of an electric field. |
