<p>This study delves into two distinct aspects of magnetic materials: investigating the impact of grain size on the magnetic circuit of an induction machine by comparing bulk FeSi with a nanostructured Fe–Si alloy with varying silicon concentrations. Initially, the magnetic properties of the induction machine's magnetic circuit are scrutinized, with parameters such as saturation magnetic flux density, coercive field, remanence, and squareness ratio meticulously analyzed. The results reveal a significant influence of grain-size parameters on magnetic behaviour, resulting in a decline in machine efficiency. In the subsequent phase, a nanostructured Fe–Si alloy is synthesized by mechanical alloying with varying silicon concentrations. State-of-the-art techniques, including scanning electron microscopy (SEM) coupled with Energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), and vibrating sample magnetometer (VSM), are employed for a comprehensive analysis of morphological, structural, and magnetic properties. Although some studies have suggested the possible formation of the Fe₃Si (suessite) phase during mechanical alloying, its occurrence in the present work remains unproven. According to the equilibrium Fe–Si phase diagram, the Fe₃Si intermetallic compound does not form within the studied range of silicon concentrations. Instead, the observed change in the lattice parameter of the Fe(Si) solid solution after milling suggests a structural transformation within the solid solution itself, likely due to the incorporation of Si atoms into the Fe lattice and the resulting distortion of the bcc structure, rather than the emergence of a new crystalline phase. Increasing silicon concentration results in reduced crystallite sizes, while lattice strain and the parameters increase by up to 3%, remaining constant thereafter. The milled samples exhibit enhanced magnetic properties, with saturation magnetization increasing as silicon concentration decreases.</p>