Carbon and Microstructure Effects on the Magnetic Properties of Fe–CN Soft Magnetic Materials (Minnealloy)

In this report, we investigated the effects of carbon and microstructure of the precursor on the magnetic performances based on a developed method for bulk preparation to synthesize Fe–CN (Minnealloy) soft magnetic materials. The melt-spun ribbons of Fe_1−xC_x were obtained to improve the efficiency of the nitrogen diffusivity by introducing porous and defects inside the grains, which increases the volume fraction of α″-Fe₁₆N₂ phase. The carbon effects were studied by the X-ray diffraction (XRD) and Wavelength-dispersive spectroscopy (WDS) to reveal the redistribution of carbon during the thermal treatment and its effects on nitridation. The microstructure variation during the thermal treatment for the Fe–C precursor was observed, which could be explained by the formation of non-uniform porous structure during the oxidation and reduction steps and also the migration of the carbon atoms.