| 摘要 |
<p>PURPOSE:To provide method and apparatus for measuring the piezo-electricity by which the piezoelectric constant of a thin piezoelectric film can be measured highly accurately without requiring measurement of material constants. CONSTITUTION:A composite material sample 10, where a piezoelectric is formed on a ferromagnetic substrate 5, is secured on a sample stage 7. Magnetic field is then applied to the composite material sample 10 by means of an electromagnetic coil 6 thus causing magnetostrictive deformation. An electric field for offsetting the magnetostrictive deformation is then applied to the sample 10 through an electric field applying means 8 while detecting the magnetostrictive deformation by means of a laser displacement gauge 9 thus returning the sample 10 back to the original stress-free state at the neutral position. Piezoelectric constant of a piezoelectric 2 is then measured based on the strength of electric field at that time and the magnetostriction constant of the ferromagnetic material 5.</p> |
