# Investigation of the Vibrational Behavior of Thermoformed Magnetic Piezoelectrets

## TL;DR

This study examines how thermoformed magnetic piezoelectrets vibrate when electrically stimulated, revealing how their structure and material properties affect their behavior.

## Contribution

The paper introduces a detailed vibrational analysis of thermoformed magneto-piezoelectrets using 3D mapping of operational modes and piezoelectric coefficients.

## Key findings

- Open channels in TMPs show pronounced resonance peaks at specific frequencies.
- Valleys in TMPs exhibit smoother responses due to enhanced damping effects.
- Vibrational heterogeneity is linked to structural and material variations as well as anisotropic coupling.

## Abstract

This study explores the vibrational behavior of Thermoformed Magneto-Piezoelectrets (TMPs), multifunctional materials consisting of thermoformed piezoelectrets with open tubular channels integrated with an additional magnetic layer. The inverse piezoelectric effect was characterized using laser vibrometry analysis, measuring the mechanical response of TMPs subjected to electrical excitation over a frequency range of 0–20 kHz. Vibrational analysis was conducted at 144 spatial points, enabling the construction of detailed three-dimensional (3D) maps of the vibration operational modes and the spatial distribution of the piezoelectric coefficient (d33). The results demonstrated significant frequency-dependent behavior, with open channels exhibiting pronounced resonance peaks, whereas valleys displayed smoother and more uniform responses due to enhanced damping effects. The observed heterogeneity in vibrational behavior is attributed to structural variations, material composition, and anisotropic coupling between the piezoelectric and magnetic properties. The findings presented in this research provide a comprehensive understanding of the development and utilization of TMPs, offering parameters for enhancing their application and supporting new discoveries in studies related to the fabrication of novel thermoformed piezoelectric sensors.