Wave Electromechanical Coupling Factor for the Guided Waves in Piezoelectric Composites.

Area of Science:

• Materials Science
• Solid Mechanics
• Electrical Engineering

Background:

• Piezoelectric composites are crucial for electromechanical applications.
• Quantifying wave-induced electromechanical coupling is essential for material design.
• Existing methods for measuring coupling factors can be computationally intensive.

Purpose of the Study:

• To introduce a novel metric, the wave electromechanical coupling factor (WEMCF), for quantifying wave coupling in piezoelectric composites.
• To develop computationally feasible formulas for calculating WEMCF.
• To validate the WEMCF against existing methods and demonstrate its utility in material design.

Main Methods:

• Proposed two definitions for WEMCF: a frequency formula and energy formulas.
• Developed a numerical tool using the wave and finite element method (WFEM) to implement energy formulas.
• Created a reduced model to accelerate wave mode and energy computations.
• Validated findings against complex one-dimensional piezoelectric composites.

Main Results:

• Demonstrated consistency between WEMCF (energy formula) and modal electromechanical coupling factor (MEMCF) with appropriate electric energy indicators.
• Achieved theoretical closure and computational feasibility for WEMCF calculation.
• Observed strong correlations between WEMCF, geometric parameters, and energy transmission loss in vibration isolation applications.

Conclusions:

• The proposed WEMCF effectively captures the physics of electromechanical coupling in guided waves.
• The energy-based WEMCF calculation is computationally feasible and suitable for complex piezoelectric composites.
• WEMCF can be a valuable tool for understanding, evaluating, and designing piezoelectric composites for diverse applications, including vibration isolation.