Vol.:(0123456789) 1 3 J Mater Sci: Mater Electron DOI 10.1007/s10854-017-8082-0 Nanostructured soft magnetic materials synthesized via mechanical alloying: a review Abdollah Hajalilou 1  · Abbas Kianvash 1  · Hossein Lavvaf 2  · Kamyar Shameli 3   Received: 6 August 2017 / Accepted: 15 October 2017 © Springer Science+Business Media, LLC 2017 behaviors of soft magnetic materials. Eventually, the mecha- nism of mechanical alloying and efect of difusivity are also highlighted. 1 Introduction Over the last few decades the interest towards soft mag- netic materials has substantially augmented due to increas- ing demand for improved performances of electromagnetic gadgets, sensors, actuators, switches, memory or data stor- age devices, etc. [1]. This causes a challenge in improving the magnetic behaviors of materials, such as saturation mag- netization (M s ), coercivity (H c ), permeability, core loss and remanence [2]. In this regards, oxide-based soft magnetic ferrites as well as their alloys are one of the major contend- ers in this feld of application. Thus, the magnetically dis- ordered ferrites characteristics have remained a subject of great interest for the last 40 years [3] On the other hand, it was hardly two decades ago that the importance and possible beneft of nanocrystalline ferrites was understood [4, 5]. Spinel ferrites, especially soft ferrites with an almost close packed face-centered cubic array of anions with holes partly flled by the cations and a general chemical formula (A)[B 2 ]O 4 where A and B designate divalent and trivalent cations, respectively [6, 7]. In terms of the cations distribu- tion, such ferrite structure can be a normal or inverse [8], depending on type of materials, preparation route, compo- sition, procedure conditions such as sintering temperature and so on [1, 6–10]. In the case of a normal spinel structure, all of the A atoms are tetrahedrally coordinated while the B atoms are octahedrally coordinated by oxygen atoms. In the case of an inverse spinel structure, the A atoms occupy half of the B sites. However, as is well known, spinels are often found with other than purely normal or purely inverse Abstract Soft magnetic materials are widely used in electrical and electronic industries due to their desirable electromagnetic features, i.e. relatively high electrical resis- tivity and low eddy current loss at high frequencies. From industrial point of view, once the size of grains is reduced to micron scale regimes, their performance is only narrowed to a few megahertz frequencies, due to their higher conductiv- ity and domain wall resonance. Thus, one way to resolve this issue and utilize these materials at high frequency applica- tions, is to reduce the size of grains from micron to sub or nanoscale before they are being compacted for sintering. In this aspect, however, several methods are employed to syn- thesize these nanoparticles, a mechanical alloying is found to be a proven route to produce a vast variety of materials with both non-equilibrium and equilibrium phases in a con- trolled size and shape of powder particles at desired ton- nages. Mechanical alloying (MA) is a solid-state powder metallurgy route which involves a repeated action of fractur- ing and re-welding of powder particles in a high-energy ball mill. The fnal products characteristics are strongly depend- ent on the variable parameters of the process, i.e. milling time, ball-to-powder weight ratio, rotation speed, grinding media and milling atmosphere. Thus, this work reviews the key role of these parameters on the structure and magnetic * Abdollah Hajalilou e.hajalilou@yahoo.com 1 Faculty of Mechanical Engineering, Department of Materials Engineering, University of Tabriz, 51666 Tabriz, Iran 2 Department of Radiation Oncology, Dana Cancer Center, University of Toledo Medical Center, 3000 Arlington Avenue, MS 1151, Toledo, OH 43614, USA 3 Malaysia-Japan International Institute of Technology (MJIIT), UTM, Kuala Lumpur 54100, Malaysia