Materials Chemistry and Physics 134 (2012) 111–115 Contents lists available at SciVerse ScienceDirect Materials Chemistry and Physics j ourna l ho me pag e: www.elsevier.com/locate/matchemphys Inﬂuence of structural transformations on functional properties of Fe 75 Ni 2 Si 8 B 13 C 2 amorphous alloy Duˇ san M. Mini ´ c b , Vladimir A. Blagojevi ´ c a , Aleksa M. Mariˇ ci´ c c , Tomáˇ s ˇ Zák d , Dragica M. Mini ´ c a,∗ a Faculty of Physical Chemistry, University of Belgrade, Belgrade, Serbia b Military Technical Institute in Belgrade, Belgrade, Serbia c Technical Faculty in Cacak, University of Kragujevac, ˇ Caˇ cak, Serbia d Institute of Physics of Materials, Academy of Sciences of Czech Republic, Brno, Czech Republic a r t i c l e i n f o Article history: Received 30 September 2011 Received in revised form 9 January 2012 Accepted 12 February 2012 Keywords: A. Amorphous materials C. Mössbauer spectroscopy D. Electrical properties D. Magnetic properties a b s t r a c t The inﬂuence of thermal treatment on functional properties of Fe 75 Ni 2 Si 8 B 13 C 2 amorphous alloy was investigated, showing the change that resulted from thermally induced structural transformations. Ther- mal history of the sample was found to have a signiﬁcant effect on magnetic properties. Structural transformations were identiﬁed using DSC and thermomagnetic curve and characterized using Möss- bauer spectroscopy and X-ray diffraction. Further investigation of magnetic and electrical properties of the alloy showed that structural relaxation prior to crystallization affected both magnetic susceptibility and electrical resistivity of the alloy, leading to an increase in both. This was caused by a conﬂuence of stress relieving and a decrease in number of defects and an increase in free volume in the alloy sample, not only enabling greater mobility of magnetic domain walls, but also decreasing electron density of states at the Fermi level. Annealing at temperatures below crystallization caused an increase in magnetic sus- ceptibility of the alloy at room temperature, however, a shift in Curie temperature was not observed. The alloy also exhibits a wide supercooled liquid region before crystallization, where its functional proper- ties remained relatively constant, exhibiting the low values of both magnetic susceptibility and electrical conductivity. © 2012 Elsevier B.V. All rights reserved. 1. Introduction Iron-based amorphous alloys have been a focus of considerable scientiﬁc interest in recent times. Their main features are homoge- nous and isotropic structure and isotropic physical and mechanical properties. Their soft magnetic properties are mainly determined by magneto-elastic and annealing-induced anisotropies [1], and they are also characterized by high corrosion resistance and good mechanical properties [2], making them suitable for use in a variety of applications, such as power devices [3,4], information handling technology, magnetic sensors [5] and anti-theft security systems [6]. Addition of metalloid amorphizers like B, Si, P or C and the sub- stitution of Fe by Co or Ni (or a mixture of both) enhance their glass forming ability [7–9], although, recently, boron-free soft magnetic alloys were prepared with magnetic properties similar to those of conventional boron-containing Fe-based alloys [10]. Addition of metallic additives like Ag, Cd or Zn has been shown to change crys- tallization kinetics and alter morphology of crystal growth in some ∗ Corresponding author. Tel.: +381 11 3336 689. E-mail addresses: dminic@ffh.bg.ac.rs, dminic2003@yahoo.com, drminic@gmail.com (D.M. Mini ´ c). amorphous alloy systems [11]. Magnetic properties of amorphous Fe-based alloys can improve signiﬁcantly after crystallization, if nanocrystalline phases are formed [12,13], producing functional materials with targeted properties. Addition of rare-earth metals like Gd, Dy or Tb has been shown to increase Curie temperature and affect the magnetic properties of iron-based amorphous alloys [14]. A study of Nb-doped FeZrB-alloys revealed that, while increase in Nb content leads to an increase the stability of amorphous alloy, it also leads to a decrease in saturation magnetization [15]. Addition of Nb also suppresses crystallization of Fe 2 B phase, allow- ing for formation of -Fe/amorphous mixed structure, leading to improved magnetic properties. Another study of iron-based amor- phous alloys found that optimized microstructure corresponds to relaxed amorphous phase and that the soft magnetic properties of these alloys can be enhanced signiﬁcantly through annealing at temperatures before crystallization [16]. As a part of multidisciplinary study of iron-based amorphous alloys, here we examined the inﬂuence of thermally induced struc- tural transformations on functional properties of Fe 75 Ni 2 Si 8 B 13 C 2 amorphous alloy. Our previous study of thermal stability and kinet- ics of this alloy [17] revealed that the crystallization of this alloy occurs in a multi-step process. These structural transformations 0254-0584/$ – see front matter © 2012 Elsevier B.V. All rights reserved. doi:10.1016/j.matchemphys.2012.02.037