US Patent 7417361 Piezoelectric/electrostrictive body, piezoelectric/electrostrictive laminate, and piezoelectric/electrostrictive actuator

There is disclosed a piezoelectric/electrostrictive body which has superior piezoelectric/electrostrictive properties and which exhibits a sufficient durability even in a case where a flexural displacement is repeated a large number of times. A piezoelectric/electrostrictive body 30 is constituted of a large number of crystal grains 31 having the piezoelectric/electrostrictive properties in the form of a film or a layer having one or more layers. A number ratio of crystal grains 32, a part of which is exposed to at least one of interfaces 35a, 35b between the bodies and the outside in a thickness direction, is 80% or more of a large number of crystal grains 31 observed in an arbitrary section in the thickness direction.