New “Damped by Scattering” Ceramic Piezocomposites with Extremally Low Q_MValues

Abstract

A new family of polymer-free ceramic piezocomposites with properties combining better parameters of PZT and PN type ceramics and 1–3 composites for wide-band NDT ultrasonic transducer applications is presented. New “damped by scattering” ceramic piezocomposites were developed based on the original microstructural design concept and characterized by previously unachievable low Q _M (Q _M ^t = 2–5) combined with high piezoelectric (d ₃₃ = 250–350) and electromechanical (k _t = 0.45–0.5) parameters, high Curie point (340°C), low acoustic impedance (15–20 MRayl) in a wide working frequency range (0.2–12 MHz). Complex sets of elastic, dielectric, and piezoelectric parameters of the new piezocomposites were systematically studied using impedance spectroscopy approach and ultrasonic method.

Keywords:

• Piezocomposite
• scattering
• losses
• dispersion