Investigation of structural, microstructural and magnetic properties of mechanically alloyed nanostructured (Fe50Co50)100 − xMox(x = 25,35) powders

This paper investigates the structural, microstructural and magnetic properties of nanocrystalline (Fe50Co50)100 − xMox [x = 25,35] powders prepared by high energy milling and then examined by X-ray diffraction, scanning electron microscopy, differential thermal analysis and vibrating sample magnetometer. The ball-milling of Fe, Co and Mo powders leads to alloying the element powders. The results showed that with increasing the milling time, the strain increases, the grain size decreases, and lattice parameter increases. Also due to the high melting temperature, hardness and low solubility of molybdenum in the iron lattice, until higher times a small amount of Mo continues to exist. Furthermore, the saturation magnetization and coercivity have the highest and the lowest values at 96 h, respectively. A suitable heat treatment on the milled powder at 96 h leads to the improvement of the magnetic properties. In this area, the saturation magnetization increases from 120 to 133 emug and 135 to 150 emug for Fe–Co-25% Mo and Fe–Co-35% Mo, respectively, and also the coercivity decreases from 30 to 10 Oe for both alloys.

The ball-milling of Fe, Co and Mo powders leads to alloying the element powders forming a small amount of Mo. The saturation magnetization and coercitvity have the highest and the lowest values at 96 h, respectively. A suitable heat treatment on the milled powder at 96 h leads to the improvement of the magnetic properties.Figure optionsDownload as PowerPoint slideHighlights
► Mechanical alloying of Fe–Co alloy by 25% and 35% Mo was done.
► A slight molybdenum remains in the system until 144 h.
► The magnetic properties are suitable at 96 h.
► The heat treatment can improve the magnetic properties noticeably.
► The obtained powders can be used for high frequencies like in rotors and stators.