Homogenized electromechanical coefficients and effective parameters of 1–3 piezocomposites for ultrasound imaging transducers

P. Tize Mha (1) , P. Maréchal (2) , G.E. E Ntamack (1) , S. Charif d'Ouazzane (3)

1 UN - Université de Ngaoundéré/University of Ngaoundéré [Cameroun]
2 LOMC - Laboratoire Ondes et Milieux Complexes
3 ENSMR - École Nationale Supérieure des Mines de Rabat

Analytical models can be useful tools to develop efficient transducers dedicated to a specific application field. This work proposes a homogenization technique for establishing the effective coefficients and parameters of 1-3 piezocomposite whose both phases are piezoelectrically active. Such piezocomposite materials may have homogenized electromechanical properties resulting from positive hybrid effect. A numerical simulation of the effective parameters resulting from a PZT-5A / PVDF-TrFE composition shows that, volume fraction influences significantly on the properties of the piezocomposite and consequently on its behaviour in service. As an end-user application for ultrasound imaging, those piezocomposite materials are effectively integrated in a piezocomposite transducer, coupled with a dedicated backing. The resulting characteristics in terms of impulse response and associated electroacoustic echo are compared and discussed for typical configurations. A method for the optimization of the design of such piezocomposite transducer is presented. Specific estimators based on the bandwidth flatness B W F and bandwidth amplitude product B W A are proposed as stable and smooth criteria for an optimization procedure.

Domaines: Acoustique [physics.class-ph]

P. Tize Mha, P. Maréchal, G.E. E Ntamack, S. Charif d'Ouazzane. Homogenized electromechanical coefficients and effective parameters of 1–3 piezocomposites for ultrasound imaging transducers. Physics Letters A, 2021, 408, pp.127492. ⟨10.1016/j.physleta.2021.127492⟩. ⟨hal-03263184v1⟩