The use of harmonic analysis of the strain response inPb(Mg1/3Nb2/3)O3-based ceramics tocalculate electrostrictive coefficients

摘要

The electromechanical response of ceramics has long been describednwith Landau Devonshire phenomenology, wherein the strain response isnlinked to a polynomial expansion in electric field or dielectricndisplacement. Consequently, the electromechanical response has beennmodeled with a variety of basis functions. However, these models havenfailed to accommodate hysteresis and the harmonic response that arisesnwith saturation phenomena. In addition, no quantitative criterion hasnbeen used to truncate the expansion. By implementing a discrete Fourierntransform in conjunction with Devonshire phenomenology, these threenproblems can be overcome as demonstrated with a dielectrically aged,nlead magnesium niobate relaxor ferroelectric well above its Tmaxn, i.e., operating in the electrostrictive regime