Formation of Iron–Cobalt Oxide Nanoparticles Using the Ball Milling Method

X-ray diffraction, Mössbauer analysis, and magnetic measurements were used to better understand the structural and magnetic properties of ball-milled Fe100-xCox compounds (x = 0, 3.5, 7.5, and 15). The effects of Co content and milling time on the iron oxidation process were investigated. Our research showed that the Fe oxidation rate increases with increasing Co content in the sample. The sizes of magnetite crystallites in samples with x = 0 and 15 were approximately 6 nm after 100 h of milling, while in samples with x = 3.5 and 7.5, they were larger than 12 nm. The saturation magnetization at room temperature after 100 h of milling was approximately 80 emu/g for samples with x = 0 and x = 15, and approximately 50 emu/g for samples with x = 3.5 and x = 7.5.