Effects of High-Energy Ball Milling on the Microwave Absorption Properties of Sr0.9Nd0.1Fe12O19

Abstract

Single-phase Nd-substituted M-type strontium hexaferrite (Sr 0.9 Nd 0.1 Fe 12 O 19 ) particles with different size distributions were prepared by ceramic conventional method followed by high-energy ball milling process. The microstructure and microwave properties of (Sr 0.9 Nd 0.1 Fe 12 O 19 ) particles were investigated by X-ray diffraction, scanning electron microscopy, laser particle size analysis, and vector network analysis techniques. Particle size decreased from 38.9 to 832 μm with increasing milling time up to 20 h, while the particle size distribution became monomodal. The bimodal distribution appeared again for the higher milling times. Microwave absorption results showed that the minimum reflection loss and band width increased from −17 to −39 dB and 1.7 to 2.4 GHz, respectively, as milling time increased up to 20 h. While the minimum reflection loss and band width decreases to −27 dB and 1.1 GHz, respectively, with more milling up to 40 h.