Plane Wave SH₀ Piezoceramic Transduction Optimized Using Geometrical Parameters.

Area of Science:

• Materials Science
• Mechanical Engineering
• Nondestructive Testing

Background:

• Structural health monitoring (SHM) offers an alternative to scheduled maintenance for critical components.
• Shear horizontal (SH 0) guided waves are ideal for SHM due to their nondispersive nature and through-thickness mode shape.
• Exciting pure SH 0 waves is challenging due to interference from other Lamb modes.

Purpose of the Study:

• To present a novel piezoelectric transducer concept optimized for pure SH 0 wave transduction.
• To enhance the modal selectivity of SH 0 waves for improved structural health monitoring applications.

Main Methods:

• Utilized a simple analytical model for initial transducer parameter exploration.
• Employed a 3D multiphysics finite element model for design refinement.
• Conducted experimental validation using a 3D laser Doppler vibrometer system.

Main Results:

• Achieved a modal selectivity of 23 dB for SH 0 waves within a 20° beam angle at 425 kHz in a 1.59 mm aluminum plate.
• Determined a 6 dB wavefront angle of 86°.
• Demonstrated excellent agreement between analytical, finite element, and experimental results.

Conclusions:

• The proposed piezoelectric transducer design effectively generates plane SH 0 waves with high purity.
• This optimized transducer design significantly advances ultrasonic guided wave structural health monitoring capabilities.