Low-frequency electromagnetic interference shielding performance of Ni–Fe coatings electrodeposited on conductive fabrics
摘要
The low-frequency electromagnetic radiation (LF-EMR) generated by high-power electric drive systems in new energy vehicles poses potential risks to human bioelectrical functions and vehicle electromagnetic compatibility. To address the lack of flexibility, lightweight and high-permeability shielding materials effective in the 1 Hz–10 kHz magnetic field range, this work constructs uniform Ni–Fe alloy coatings on conductive fiber fabrics via an optimized electrodeposition strategy. A systematic L25 (53) orthogonal design reveals current density as the dominant factor governing coating compactness, Ni/Fe co-deposition behavior, and magnetic shielding performance, followed by temperature and pH. Under the optimal conditions (30 °C, pH 3.5, 3 A·dm⁻2), the Ni–Fe coating exhibits a dense microstructure, strong interfacial adhesion, and uniform elemental distribution, achieving an average shielding effectiveness (SE) of ~ 8 dB at 10 kHz with a thickness of 28.3 um—corresponding to ~ 70% attenuation of magnetic field intensity. Thickness-dependent analysis confirms that magnetic flux shunting arising from the high permeability of the Ni–Fe alloy dominates the shielding mechanism in the low-frequency regime, whereas eddy-current losses are minimal. Environmental stability tests demonstrate that the coatings maintain structural integrity and SE after high-temperature exposure, bending cycles, and water immersion. Frequency-dependent permeability derived from LCR measurements was incorporated into CST simulations, which showed excellent agreement with the experimental data and predicted broadband shielding capabilities of 33–91 dB in 10 kHz–30 MHz range. This study provides a practical, scalable, and mechanically flexible high-permeability coating system for low-frequency magnetic shielding in new energy vehicle applications.