Enhanced anticorrosive and electromagnetic shielding performances of Nickel nanoparticles/SA/PEO composite coating on 6061 aluminum alloy

Plasma electrolytic oxidation (PEO) coatings have excellent corrosion, wear resistance and mechanical properties, but the poor dielectric and magnetic properties of metal-ceramic coatings limit their application in electromagnetic shielding. In this work, a novel composite process (PEO and impregnation reduction) was designed to prepare multifunctional composite coatings on the surface of 6061 aluminum alloy with both hydrophobic, corrosion resistance and high electromagnetic shielding properties, offering a novel material solution for addressing equipment protection challenges in complex electromagnetic environments. Specifically, the samples demonstrated a notable improvement in the absorption loss effectiveness when compared to the 6061aluminum alloy, achieving an absorption electromagnetic shielding performance of 34.1 dB and a high electromagnetic shielding performance of 42.3 dB in the X-band (8.2–12.4 GHz). Furthermore, the Ni/SA/PEO composite coatings exhibit superior hydrophobicity and corrosion resistance. After 96 h of immersion in 3.5 wt% NaCl solution, the Electromagnetic Interference (EMI) shielding performance is essentially unchanged, demonstrating the exceptional durability of the Ni/SA/PEO composite coatings in hostile environments. The preparation of the composite coating provides new possibilities for the study of multifunctional electromagnetic shielding coatings. • A multifunctional coating was prepared using PEO and immersion reduction process. • Coating has high electromagnetic shielding performance of 42.3 dB in the X band. • Electromagnetic shielding performance remains stable in corrosive environments