Magnetic behaviour and percolation in mechanically alloyed Fe–SiO2 granular solids

Alonso-Sañudo, M; Blackwell, Jennifer; O’Grady, K.; González, J.M.; Cebollada, F.; Morales, M.P.

doi:10.1016/s0304-8853(00)00379-6

Cited by 16 publications

(8 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The magnetization processes of the continuous epitaxial Fe films, when studied along an easy MAE direction [100], are characterized by square hysteresis loops with low coercivity, between 20 and 40 Oe, and very narrow switching field distribution (SFD), with full width at half maximum about 1 Oe, approximately (the SFD of a high remanence, square loop is basically proportional to the differential susceptibility of its demagnetization branch [14]). This narrow switching process relies on the nucleation of one or just a few reversed nuclei that sweep the whole film when the field reaches the coercive force value [9,15].…”

Section: Resultsmentioning

confidence: 99%

Control of magnetization reversal by combining shape and magnetocrystalline anisotropy in epitaxial Fe planar nanowires

et al. 2010

Self Cite

View full text Add to dashboard Cite

This work presents an analysis of the in-plane magnetization reversal mechanisms of Fe nanowires, with widths from 100 nm to 1 microm, fabricated in epitaxial Au(001)/Fe(001)/MgO(001) thin films by means of focused ion and electron beam lithographies, with either positive or negative resist. The experimental results show that the switching mechanisms and hysteresis are almost exclusively functions of the dimensions of the wires and of the Fe intrinsic properties, with minor influence of the specific fabrication route employed upon optimization of nanostructure parameters in terms of crystallinity and morphology, and well defined and reproducible geometry. The reversal processes evolve from wall pinning at low angles between the applied field and the axis of the wires to basically uniform magnetization rotation at high angles. This behaviour can be described in terms of single spin configurations, thus ruling out the formation of multidomain structures even at high angles. The ability to achieve these high quality and well controlled nanowires allowed us to develop an analytical model, based on uniform magnetization configurations considering just the intrinsic Fe properties and the shape and dimensions of the wires. This simple approach provides a very good qualitative and quantitative agreement with the experimental results, thus evidencing the relatively small role of other extrinsic factors in the magnetization processes.

show abstract

Section: Resultsmentioning

confidence: 99%

Control of magnetization reversal by combining shape and magnetocrystalline anisotropy in epitaxial Fe planar nanowires

et al. 2010

Self Cite

View full text Add to dashboard Cite

show abstract

“…The shift to higher fields in the SFD (and the increase in coercivity) with decreasing magnetic phase content in magneticÀnonmagnetic composites is a general trend due to the presence of higher dipolar fields and stronger pinning centers associated with the magneticÀnonmagnetic borders. [12] The magnetoelastic coupling of the magnetization with the internal stresses might also play a role in the magnetic hardening of the composites.…”

Section: Resultsmentioning

confidence: 99%

Dielectric and magnetic characterization of the mixed system (BaTiO₃)_x(NiFe₂O₄)₁₋_x

et al. 2015

View full text Add to dashboard Cite

Ceramic composites of the mixed system (BaTiO 3 ) x (NiFe 2 O 4 ) 1¡x (x D 1, 0.8, 0.65, 0.6, 0.5, 0.2, 0) have been prepared by hydrothermal synthesis and characterized through dielectric and magnetic measurements. It is shown that, when compared with the first-order phase transition of pure BaTiO 3 , the ferroelectric response of this mixed system is dramatically smeared by the presence of ferrite and eventually disappears around x % 0.65. The peak of the dielectric constant becomes increasingly smoothed with composition, also diminishing its maximum value as the frequency increases. Moreover, the magnetic behavior is not suppressed by the presence of the ferroelectric perovskite and just qualitative changes occur in the hysteresis parameters on the whole compositional range.

show abstract

“…The diffraction peaks are becoming weaker and significantly broader, as predicted for a continued decrease of particle/crystallite size and gradual micro-strain (defects) occurring within the milling operation [19]. A large peak during a long milling time is caused by the silica's amorphous structure owing to its lower peak intensity compared with the Fe peaks [26]. The absence of several SiO 2 peaks is attributed to that the mass absorption coefficient of Fe (310.94 cm 2 g −1 ) is substantial compared to SiO 2 (34.84 cm 2 g −1 ).…”

Section: Structural Investigationmentioning

confidence: 86%

The impact of Cu, Ni and Fe₂O₃ on the magnetic behavior and structural properties of FeSiO₂ nanocomposite synthesized through ball milling

Younes,

Amraoui,

Manseri

et al. 2023

Phys. Scr.

View full text Add to dashboard Cite

The nanocomposite Fe-A/SiO2 soft magnetic materials, with Cu, Ni, and Fe2O3 as dopants, were produced using a mechanical alloying technique. Our central objective was to explore the impact of process parameters on Fe/SiO2 nanocomposite properties. We assessed varying milling time and dopant addition rates, analyzing structural, morphological, and magnetic aspects through SEM, EDS, XRD, and VSM at different synthesis stages. The XRD pattern revealed iron, Fe(Ni), Fe(Cu), and Fe2O3 with an average crystallite size of 28–39 nm and lattice strain of 0.0097%–0.0222%. Notably, the lattice parameters decreased from 0.2852 to 0.2836 nm. Among nanocomposites, FeCu/SiO2 displayed the smallest crystallite size (34.3 nm), while FeNiSiO2 showed the highest lattice parameter (0.2853 nm). The ATR analysis unveiled Si–O–Si stretching vibrations at 1052 cm−1, intensifying with milling time. The inclusion of Cu and Ni in the FeSiO2 system significantly influenced the Si–O–Si bond. Coercivity and remanence magnetization in Fe/SiO2 increased notably with milling time, reaching 68.47 Oe and 8.73 emu g−1, respectively. The Fe/Fe2O3/SiO2 and FeSiO2 nanocomposites exhibited the maximum values of coercivity (47.07 Oe) and remanence magnetization (12.24 emu g−1). Remarkably, the Fe/SiO2 nanocomposite displayed the highest saturation magnetization, measuring an impressive 176.07 emu g−1 after 30 h of milling, while FeCu/SiO2 reached 165.64 emu g−1 after 20 h. Overall, our findings suggest the Fe/SiO2 nanocomposite as a promising high-frequency soft magnetic material.

show abstract

Magnetic behaviour and percolation in mechanically alloyed Fe–SiO2 granular solids

Cited by 16 publications

References 11 publications

Control of magnetization reversal by combining shape and magnetocrystalline anisotropy in epitaxial Fe planar nanowires

Control of magnetization reversal by combining shape and magnetocrystalline anisotropy in epitaxial Fe planar nanowires

Dielectric and magnetic characterization of the mixed system (BaTiO₃)_x(NiFe₂O₄)₁₋_x

The impact of Cu, Ni and Fe₂O₃ on the magnetic behavior and structural properties of FeSiO₂ nanocomposite synthesized through ball milling

Contact Info

Product

Resources

About

Magnetic behaviour and percolation in mechanically alloyed Fe–SiO2 granular solids

Cited by 16 publications

References 11 publications

Control of magnetization reversal by combining shape and magnetocrystalline anisotropy in epitaxial Fe planar nanowires

Control of magnetization reversal by combining shape and magnetocrystalline anisotropy in epitaxial Fe planar nanowires

Dielectric and magnetic characterization of the mixed system (BaTiO3)x(NiFe2O4)1−x

The impact of Cu, Ni and Fe2O3 on the magnetic behavior and structural properties of FeSiO2 nanocomposite synthesized through ball milling

Contact Info

Product

Resources

About

Dielectric and magnetic characterization of the mixed system (BaTiO₃)_x(NiFe₂O₄)₁₋_x

The impact of Cu, Ni and Fe₂O₃ on the magnetic behavior and structural properties of FeSiO₂ nanocomposite synthesized through ball milling