Optimized orientation of PIN–PMN–PT single crystal for enhanced electromechanical properties via anisotropic structural engineering

To enhance the performance of medical ultrasonic transducers, we optimized the cutting angle of length orientation for the [011]-oriented Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 single crystal (SC) B-mode resonator to maximize the longitudinal vibration (k′33) while suppressing transverse vibration (k31) via anisotropic structural engineering. Experimental results demonstrate that a 60° length orientation along the [100]c direction achieves a peak k′33 value of 77.8%, corroborating theoretical predictions. This orientation of resonator’s length concurrently delivers a low acoustic impedance (Z′33) of 27.6 MRayl, a broad 3 dB bandwidth of 77.1%, and excellent transmit (TP = 3.24 × 10−4 m⋅N−1/2) and receive (RP = 3.77 × 10−11 m⋅N−1/2) efficiencies. The synergy of high electromechanical coupling and reduced clamped dielectric permittivity (ε33S/ε0 < 600) renders this configuration ideal for large-aperture, high-frequency ultrasonic transducers. This work underscores the critical role of crystallographic orientation in tailoring anisotropic electromechanical properties, establishing guidelines of material design for developing high-performance transducers.