Piezoelectric / electrostrictive ceramic composition and displacement generator

摘要

A piezoelectric / electrostrictive body having a large electric field induced strain and high durability against an electric field in the direction opposite to the polarization direction is obtained. The composition of the piezoelectric / electrostrictive ceramic is represented by the general formula Pba {ZnbSbc (ZrdTi1-d) 1-bc} O3. a, b, c and d are 0.985 ≦ a ≦ 0.998, 0.010 ≦ b ≦ 0.040, 0.025 ≦ c ≦ 0.090, 0.460 ≦ d ≦ 0.510 and 2 125 ≦ c / b ≦ 3.000 is satisfied. An auxiliary component containing at least one element selected from the group consisting of Mn, Cr, Fe and rare earth elements may be added to the main component. The amount of at least one element added to 100 parts by weight of the main component is 0.3 parts by weight or less in terms of oxide.