Love Wave Propagation in a Piezoelectric Composite Structure with an Inhomogeneous Internal Layer

Area of Science:

• Materials Science
• Solid Mechanics
• Acoustics

Background:

• Inhomogeneous internal strata arise from thermal gradients, material interactions, diffusion, or degradation.
• These strata can be modeled as functional graded (FG) piezoelectric materials.
• Understanding their impact on wave propagation is crucial for device performance.

Purpose of the Study:

• To investigate the effect of FG piezoelectric materials on Love wave propagation.
• To develop and apply a power series technique for solving governing equations.
• To analyze the influence of material inhomogeneity, damage, and bonding on wave characteristics.

Main Methods:

• Linear piezoelectric theory and a power series technique were employed.
• Two-dimensional partial differential equations with variable coefficients were solved.
• Numerical analysis systematically explored the influence of graded material properties.

Main Results:

• Material inhomogeneity affects phase velocity, electromechanical coupling factor, and displacement distribution.
• Piezoelectric damage and material bonding influence higher modes and fundamental Love mode characteristics.
• Specific effects include earlier appearance of higher modes and decreased phase velocity.

Conclusions:

• The power series method is general for FG materials with varying coefficients.
• Inhomogeneity and damage significantly alter Love wave propagation.
• Results provide theoretical guidance for designing surface acoustic wave devices and sensors.