PIEZOELECTRIC/ELECTROSTRICTIVE FILM TYPE ELEMENT

摘要

PROBLEM TO BE SOLVED: To improve the reliability of a piezoelectric/electrostrictive film type element and prolong the useful period of the element by eliminating the need for a special circuit from the element, by making the deterioration of displacement suppressible even when the element is driven for a long period by widening the range of its effective driving electric field from a negative electric field to a positive electric field. SOLUTION: The piezoelectric/electrostrictive film type element 10 is provided with a piezoelectric/electrostrictive layer 24 and at least a pair of electrodes 26a and 26b formed on the layer 24. The layer 24 contains Mn in a Pb- containing perovskite type piezoelectric/electrostrictive material in an amount of 0.1-0.5 wt.% in terms of MnO2 . To be concrete, the layer 24 is constituted of a Pb(Mg1/3 Nb2/3 )O3 -PbZrO3 -PbTiO3 -based perovskite type piezoelectric/ electrostrictive maternal the Pb of which is partially replaced with Sr and which contains Mn in an amount of 0.1-0.5 wt.% in terms of MnO2 .