A piezoelectric ceramic material, sintered, a piezoelectric ceramic compact and piezoelectric ceramic device

摘要

It is provided a peizoelektrischer ceramic material, from which a sintered piezoelectric ceramic green compact with a low electric and mechanical coupling coefficient, a low resonant impedance and a low temperature dependence of the resonance frequency can be produced. The piezoelectric ceramic material is a solid solution consists with a primary, which are composed of pbtio φ 3 φ, pbzro φ 3 φ and pb (ma φ × φ md φ y φ) o φ 3 φ, where ma at least one two - or trivalent element, and md at least one of five - or hexavalent element, and the ratio x / y of the ma - proportion x to the md - portion y is greater than the stoichiometric ratio is. Ma is preferably mn, md, at least one element selected from the group consisting of nb, sb, ta and w, and it is true 0,525 a / (b + c + d + 2e) 1, when the respective proportion of mn, nb, sb, ta and w, for example, by a, b, c, d or e is represented and an amount of substance of the element pb of about 20 mol percent or less by at least one element from the group consisting of ca, ba, sr and la existing group is replaced. Preferably, the production of a sintered compact in such a way that this piezoelectric ceramic material in an oxygen atmosphere, under an oxygen concentration with a proportion by volume of about 80% or more is fired and in the unsaturated polarized state with an electromechanical coupling factor is used, the approximately 80% or less of the coupling factor of a sintered compact ..