Design and fabrication of relaxor-ferroelectric single crystal PIN–PMN–PT/epoxy 2–2 composite based array transducer

• Highly performed ferroelectric single crystal PIMNT has been used.
• PIMNT/epoxy 2–2 composite has been designed and fabricated.
• Excellent piezoelectric properties have been achieved.
• Array transducer with broad bandwidth (127.7% @-6 dB) has been designed and fabricated.

In order to improve the applicability of Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 (PIN–PMN–PT) single crystal and make full use of relaxor ferroelectric single crystal based array transducer on high frequency, PIN–PMN–PT/epoxy 2–2 composite with the width-to-height ratio G of 0.5 in single crystal beam was prepared by a dice-and-fill method. Excellent properties for the fabrication of ultrasonic transducer has been achieved, where ultrahigh thickness electromechanical coupling coefficient (kt), ultrahigh effective electromechanical coupling coefficient (keff), relatively high piezoelectric constant (d33), and low acoustic impedance (Z) are 86%, 88.4%, 1200 pC/N and 21 MRayls, respectively. Based on the improved flexibility of as-prepared PIN–PMN–PT/epoxy 2–2 composite, a 12-element array transducer with the center frequency of 10 MHz has been designed, fabricated and characterized. The high frequency array transducer has achieved an ultra-broad bandwidth (@-6 dB) of 127.7%. It is worth mentioning that all 12 elements in the array work very well. The array transducer based on PIN–PMN–PT/epoxy composite exhibits excellent uniformity, confirming that the relaxor ferroelectric single crystal based 2–2 composite can be used to develop high-performance array transducer in the field of high frequency application.