Low-Carbon-Residue Multi-Principal-Element Magnetic Alloys for Excellent Microwave Absorption

Area of Science:

• Materials Science
• Electromagnetism
• Nanotechnology

Background:

• Magnetic alloy/carbon composites are effective microwave absorbers due to interfaces and loss mechanisms.
• Challenges exist in reducing carbon content while ensuring uniform magnetic component distribution.

Purpose of the Study:

• To develop a spray-drying strategy for synthesizing low-carbon magnetic alloy/oxide microspheres.
• To achieve uniform magnetic phase distribution and enhance microwave absorption properties.

Main Methods:

• Utilized a spray-drying technique with controlled nitrate precursor ratios.
• Optimized thermal treatment to synthesize alloy/oxide microspheres.
• Analyzed material composition, microstructure, and electromagnetic properties.

Main Results:

• Synthesized low-carbon alloy/oxide microspheres with uniformly distributed magnetic phases.
• FeCuMn system achieved -48.2 dB minimum reflection loss at 1.5 mm thickness.
• FeCuAl system exhibited an ultra-broad effective absorption bandwidth (EAB) of 5.12 GHz.
• FeAlMn system demonstrated superior polarization miniaturization for thin-film absorption.

Conclusions:

• The spray-drying strategy effectively produces low-carbon magnetic composites with tunable properties.
• Optimized composition and structure lead to exceptional microwave absorption performance.
• This approach offers a practical method for designing advanced electromagnetic composite structures.