Significant improvement in stability and resolution of Metglas/PVDF magnetoelectric sensor via Kapton interlayer integration

Abstract

The rapid advancement of the Internet of Things has significantly escalated the demand for high-performance magnetic sensors, where resolution and stability are paramount. In recent years, flexible Metglas/polyvinylidene fluoride (PVDF) magnetoelectric sensors have emerged as a mature technology with practical applications. However, the substantial disparity in Young’s modulus between the Metglas and PVDF layers leads to vibration instability, which detrimentally affects the sensor’s resolution. To mitigate this issue, this study proposes the integration of a Kapton layer between the Metglas and PVDF layers. This innovative approach aims to enhance the sensor’s linearity, resolution, and cyclic stability while preserving its inherent flexibility. Finite element simulations reveal the dual-effect of the Kapton layer: its elastic modulus gradient design ensures uniform redistribution of the stress field, while its mechanical damping properties suppress vibration and noise during dynamic testing. The fabricated Metglas/Kapton/PVDF trilayer magnetoelectric sensor demonstrates remarkable performance metrics, achieving a linearity of 99.962% and a resolution of 0.047 nT. The output voltage fluctuation amplitude (ΔVOUT < 2 mV) after ten repeated measurements is reduced by 76.5% compared to the bilayer sensor, and the standard deviation decreases from 2.65 to 0.6. These enhancements enable the flexible magnetoelectric sensor to detect weaker magnetic field variations, greatly improving measurement accuracy.