Applications of flexible ultrasonic transducer array for defect detection at 150 °C.

In this study, the feasibility of using a one dimensional 16-element flexible ultrasonic transducer (FUT) array for nondestructive testing at 150 °C is demonstrated. The FUT arrays were made by a sol-gel sprayed piezoelectric film technology; a PZT composite film was sprayed on a titanium foil of 75 µm thickness. Since the FUT array is flexible, it was attached to a steel pipe with an outer diameter of 89 mm and a wall thickness of 6.

Design and fabrication of an integrated dual-mode ultrasonic probe.

In this paper, we present an integrated dual-mode ultrasonic probe that is capable of transmitting and receiving longitudinal and shear waves (LW and SW, respectively) simultaneously. The probe consists of a thick piezoelectric film LW ultrasonic transducer and a substrate with a specific shape. An SW is generated inside the substrate by mode conversion.

Ultrasonic probes having three orthogonal polarizations.

Ultrasonic probes which can simultaneously generate and receive 2 orthogonal polarized shear (S(perpendicular) and S(//)) and longitudinal (L) waves in screw shape have been presented. Thick piezoelectric films are directly fabricated onto the heads of such probes as L wave integrated ultrasonic transducers. S(perpendicular) and S(//) waves are obtained using mode conversion method.

Integrated high-temperature piezoelectric plate acoustic wave transducers using mode conversion.

Piezoelectric thick (>66 microm) films have been directly coated onto aluminum (Al) substrates using a sol-gel spray technique. With top electrode, these films serve as integrated ultrasonic transducers (IUT), which normally operate as thickness longitudinal wave transducers. When such IUT are located at the edges of the metallic plates, they can excite and detect symmetrical, antisymmetric and shear horizontal types of plate acoustic waves (PAW) using mode conversion methods.