Analysis of micro machinable piezoelectrically driven one dimensional flexural transducers

Flexural piezoelectrically driven transducers are of interest as they may couple efficiently to fluids, and could be realized for high frequencies using micromachining techniques. Arrays of essentially one dimensional elements are attractive as they may have small inactive boundary areas. We present an analytical theory for such elements. It may handle arbitrarily layered plate structures with one or more piezoelectric layers included, varying along the plate, and is valid also for higher harmonics. It includes shear deformation, effects of residual stress in the plate, and bending effects at height differences between plate elements. The analysis is compared both to experiments on a low frequency (140 kHz) PZT brass structure, and to FEM analysis. FEM is also used to determine realistic edge boundary conditions for the structure. The theory matches well with the FEM analysis for plate resonance´s, and is in reasonable agreement with experiments