Structural and shielding effectiveness properties of (NiFe₂O₄/chopped strands) composites for 6.5–18 GHz applications

In this research, a mixed oxide technique was employed to create composite materials comprising NiFe₂O₄-chopped strands, aimed at evaluating their structural properties and microwave shielding effectiveness. The composites, produced through a hot-pressing process with varying proportions of NiFe₂O₄ and chopped strands, were integrated with epoxy to enhance their shielding capabilities. X-ray diffraction confirmed the formation of single-phase NiFe₂O₄, free from secondary phases. Scanning electron microscopy analysis corroborated the presence of cubic crystalline NiFe₂O₄, without microstructural impurities. The microwave shielding performance of the composites was assessed within the 6.5–18 GHz frequency range using a network analyzer (NA), revealing a minimum shielding effectiveness of − 36.34 dB at 16.56 GHz for a 1.3 mm thick sample. These findings demonstrate the successful fabrication of NiFe₂O₄-chopped strands composites with tunable microwave shielding properties, achieved by adjusting the NiFe₂O₄ content, allowing for tailored performance across various frequency bands.