Process control agent effect on the structural and magnetic properties of mechanically alloyed Fe(Al) disordered system

•The effects of ethanol during the mechanical alloying of Fe(Al) were investigated.•Fe(Al) disordered phase was reached after 6 hours of milling at 25 Hz without ethanol .•No presence of ethanol provokes high adherence of the powders to the milling tools..•Ethanol addition allowed a recovery rate of the initial mixed powders up to 96%.•Ethanol inhibits the Fe(Al) phase formation even for prolonged milling times. The effect of ethanol as a process control agent (PCA) on the mechanical alloying (MA) of Fe-20 at. % Al powders is presented. MA was performed at room temperature in an oscillation ball mill and its dynamic was studied by changing the milling frequency and time. We characterized the milled powders using X-ray diffraction (XRD), Mössbauer spectroscopy, and vibrating sample magnetometry (VSM). X-ray patterns for the milled powders without PCA showed a rapid formation of the disordered Fe(Al) solid solution after 25 Hz for 6 h of milling. Mössbauer spectroscopy confirmed two ferromagnetic sites related to the α-Fe phase and Fe(Al) disordered solid solution. However, intense cold welding of the powders to the milling tools for all milling frequencies led to a powder recovery of only 40% on average. The addition of ethanol as a PCA at a 25 Hz increased the powder recovery up to 96% even for different milling times, whereas X-ray diffraction and Mössbauer spectra showed a single α-Fe phase. VSM results exhibit the presence of a soft ferromagnetic character, in which a correlation between the structural parameters with the coercive field and saturation magnetization was deduced. Thus, while ethanol increases the powder recovery rate it also modifies the milling kinetics affecting the domain walls’ movement and the corresponding magnetic interactions between iron atoms.