Dual-silicon-source engineered FeSiBCr/SiO2 amorphous soft magnetic composites with enhanced corrosion resistance and magnetic properties

For amorphous soft magnetic composites (ASMCs), achieving both enhanced magnetic properties and corrosion resistance in harsh environments remains a significant challenge. In this paper, we adopt a dual-silicon-source strategy to fabricate high-performance FeSiBCr/SiO₂ ASMCs, where a uniform SiO₂ insulation layer is formed on the surface of FeSiBCr particles by using 3-aminopropyltriethoxysilane as a surface modifier and tetraethyl orthosilicate as a hydrolysis precursor. The SiO₂ insulation layer significantly elevates the interfacial potential of FeSiBCr particles, effectively inhibiting electron release and retarding anodic oxidation. Meanwhile, it enhances hydrophobicity and suppresses corrosive reactions by isolating the matrix from aggressive media. Notably, the corrosion resistance of FeSiBCr/SiO₂-0.45 wt.% ASMC is significantly improved. Simultaneously, FeSiBCr/SiO₂-0.45 wt.% ASMC exhibits stable effective permeability of 22.6 within 452 MHz, high direct current bias of 87.7%, wide cut-off frequency of 1.4 GHz, and low power loss of 183.58 mW/cm³ (0.05 T/100 kHz). This paper provides a facile approach to designing corrosion-resistant ASMCs with superior magnetic properties, demonstrating broad application potential in harsh environments.