Elsevier

Advanced Powder Technology

Volume 29, Issue 9, September 2018, Pages 2188-2193
Advanced Powder Technology

Original Research Paper
Steady-shear magnetorheological response of fluids containing solution-combustion-synthesized Ni-Zn ferrite powder

https://doi.org/10.1016/j.apt.2018.06.002Get rights and content

Highlights

  • Soft magnetic Ni0.5Zn0.5Fe2O4 (NZF) powder was synthesized via solution combustion route.

  • Magnetorheological fluids (MRFs) were prepared using the NZF powder in silicon oil.

  • Yield stress and viscosity of MRFs increase with magnetic field and particle content ϕ.

  • Interlocking of irregular shaped particles aid in non-linear increment of yield stress.

  • Among all, the MRF with ϕ = 0.2 shows the highest efficiency above 0.4 T.

Abstract

Magnetically soft nickel-zinc ferrite (Ni0.5Zn0.5Fe2O4) powder with high saturation magnetization was synthesized by solution combustion route using metal nitrates as precursors and glycine as fuel. The particles were found to have irregular morphology. Three different concentrations of magnetorheological fluids (MRFs) were prepared by dispersing 10, 20 and 40 wt% of these particles in thin silicone oil. The behaviours of the MRFs were studied under steady shear conditions at different applied magnetic field strengths (B). The yield strength (τY) and viscosity (η) of all the MRFs were found to increase with B and particle fill fraction ϕ, while the response of the MRFs was strongly influenced by the morphology, microstructure and saturation magnetization of the particles. Owing to the low density of the particles, the observed off-state viscosity is high. However, the excellent thermo-oxidative and chemical stabilities of these magnetic oxide particles than metallic magnetic particles make these MRFs dependable for applications in harsh working environments. In addition, the low cost and feasibility of large scale preparation of these magnetic oxides make these MRFs further attractive for industrial applications.

Introduction

Magnetorheological fluids (MRFs) are smart fluids which have the ability to tune their viscosity reversibly in split-second time, via an externally applied magnetic field. This unique ability makes the MRFs useful for applications involving mechanical shock mitigation and vibration damping, without any permanent failure. The most relevant magnetorheological parameter deciding the efficiency of mechanical impact addressal is the yield strength developed in the MRF on magnetic activation. Conventionally, a high yield strength value can be expected from the MRFs containing metallic magnetic (Fe, Co, Ni or their alloys) particles having high saturation magnetization [1], [2], [3], [4], [5]. However, MRFs containing these metallic particles suffer from poor dispersion stability and extremely difficult redispersibility post-sedimentation in carrier fluid as well as chemical instability in ambience/work environments. Although there are methods to circumvent these issues by making use of additives to MRFs [6], [7], [8], [9], [10], [11], [12] or coating the particles [13], [14], [15], [16], [17], these deteriorate the magnetic properties of particles leading to a decrease in speed of response of the MRF. Moreover, cumbersome synthesis [3], [4], [18], [19], [20], [21] and stringent conditions of preservation of the functional magnetic particles add to the cost of such MRFs, limiting the feasibility of their industrial scale usage.

Hence, in our present work, we investigate the magnetorheological response of MRFs containing an alternate magnetic oxide powder, i.e., Ni-Zn ferrite particles. The interest in choice of Ni-Zn ferrite powder is due to its excellent chemical and thermo-oxidative stabilities and low mass-density (which eliminates the need of additives or coating agents in the MRF). Furthermore, this method of production is highly economical with low (a few minutes) production time, which is industry-friendly. Unlike metallic (such as Fe) particles, the preservation of the Ni-Zn ferrite sample is easy. In addition to the fact that synthesis of Ni-Zn ferrite by solution combustion technique [22], [23] needs no sophisticated techniques, it is a reproducible method which uses low-cost precursors. In this study, we have chosen a specific composition, Ni0.5Zn0.5Fe2O4, due to its best magnetic properties (compared to all other compositions of Ni-Zn ferrites) in terms of saturation magnetization and magnetic softness [24].

Besides their good magnetorheological property, the MRFs containing ferrimagnetic oxide particles also show enhanced dispersion stability against sedimentation due to their low density. There are noteworthy works on magnetorheological fluids based on calcium ferrite nano-crystal clusters [25], manganese ferrite/graphene oxide nanocomposites [26] and highly magnetic zinc ferrite nano-crystal clusters [27].

In the forthcoming sections, we discuss the synthesis procedure of Ni-Zn ferrite powder and its structural, morphological and magnetic properties. This is succeeded by the details on preparation of MRFs and their magnetorheological characterization under steady-state shear conditions, at different applied magnetic field strengths. The magnetorheological parameters viz. yield strength, ratios of on-state to off-state viscosities of MRFs, their significance and the relationship between these parameters to particle microstructure and magnetic nature are discussed.

Section snippets

2.1 Synthesis of Ni0.5Zn0.5Fe2O4 powder and preparation of MRFs

Ni-Zn ferrite powders of different compositions can be synthesized by various methods [28], [29], [30], [31], [32], [33], [34], [35], [36], however, the choice of synthesis depends on the required physical and magnetic properties of the product phase. Solution combustion method initially employed by Hwang et al [37] was a two-step process, which involves an initial sol–gel auto-ignition process followed by calcination at an elevated temperature to obtain crystalline ferrite powder with high

Results and discussion

The XRD pattern (Fig. 1(a)) confirmed the formation of pure phase spinel (Fd3-m) structured Ni0.5Zn0.5Fe2O4. The Miller indices corresponding to the Bragg reflections of the XRD pattern are shown in Fig. 1(a). The Rietveld refinement of cation occupancy confirmed the stoichiometric phase. The lattice parameter (a) and crystallite size (L) determined by applying Scherrer formula (for (3 1 1) Bragg peak of NZFP) are 8.4399 Å and 34.2 nm, respectively. The X-ray density of NZFP sample was

Conclusions

Soft-magnetic Ni0.5Zn0.5Fe2O4 powder having irregular particle morphology was prepared using industrially scalable solution combustion synthesis method. The MRFs were prepared by dispersing these particles in thin silicone oil at different weight fractions. The dynamic yield stresses of the MRFs estimated by Bingham plastic model fit of the obtained flow curves showed strong dependence of yield strength on the morphology and magnetic nature of particles. The Ni-Zn ferrite powder based MRF

Acknowledgement

BS is grateful for the financial support received from the sponsored research program of ISRO-IISc Space Technology Cell (Code number: ISTC/CMR/BS/355). The authors thank Mr. Venkataiah (Chemical Engineering, IISc, Bangalore) for facilitating the magnetorheometer.

References (59)

  • C.C. Hwang et al.

    Combustion synthesis of Ni–Zn ferrite by using glycine and metal nitrates-investigations of precursor homogeneity, product reproducibility, and reaction mechanism

    Mater. Chem. Phys.

    (2005)
  • R.A. Brand

    Improving the validity of hyperfine field distributions from magnetic alloys: Part I: Unpolarized source

    Nucl. Instrum. Methods B

    (1987)
  • R.A. Brand

    Improving the validity of hyperfine field distributions from magnetic alloys: Part II: Polarized source and spin texture

    Nucl. Instrum. Methods B

    (1987)
  • V.J. Angadi et al.

    Composition dependent structural and morphological modifications in nanocrystalline Mn-Zn ferrites induced by high energy gamma-irradiation

    Mater. Chem. Phys.

    (2017)
  • N. Thomas et al.

    Comparative study of the structural and magnetic properties of alpha and beta phases of lithium ferrite nanoparticles synthesized by solution combustion method

    J. Magn. Magn. Mater.

    (2018)
  • A.V. Anupama et al.

    Synthesis of coral-shaped yttrium-aluminium-iron garnets by solution-combustion method

    Cer. Intl.

    (2018)
  • V.J. Angadi et al.

    Evidence of structural damage in Sm and Gd co-doped Mn-Zn ferrite ceramics due to high-energy gamma irradiation

    Cer. Intl.

    (2016)
  • Z. Cao et al.

    Preparation of superparamagnetic Fe3O4/PMMA nano composites and their magnetorheological characteristics

    J. Magn. Magn. Mater.

    (2008)
  • A.J. Margida et al.

    Magnetorheological materials based on iron alloy particles

    Int. J. Mod. Phys. B

    (1996)
  • J. de Vicente et al.

    Effect of particle shape in magnetorheology

    J. Rheol.

    (2010)
  • A.G. Ramírez et al.

    Influence of particle shape on the magnetic and magnetorheological properties of nanoparticle suspensions

    Soft Matter

    (2009)
  • F.F. Fang et al.

    Novel magnetic composite particles of carbonyl iron embedded in polystyrene and their magnetorheological characteristics

    IEEE Trans. Magn.

    (2008)
  • M.T.L. López et al.

    Sedimentation and redispersion phenomena in iron-based magnetorheological fluids

    J. Rheol.

    (2006)
  • K.D. Weiss, D.A. Nixon, J.D. Carlson, A.J. Margida, Thixotropic Magnetorheological Materials, US Patent No. 5645752,...
  • J. de Vicente et al.

    Rheological study of the stabilization of magnetizable colloidal suspensions by addition of silica nanoparticles

    J. Rheol.

    (2003)
  • P.P. Phulé et al.

    Synthesis and properties of novel magnetorheological fluids having improved stability and redispersibility

    Int. J. Mod. Phys. B

    (1999)
  • S. Lim et al.

    Magnetorheological characterization of organoclay added carbonyl-iron suspensions

    Int. J. Mod. Phys. B

    (2005)
  • S.T. Lim et al.

    Magnetorheological characterization of carbonyl iron-organoclay suspensions

    IEEE Trans. Magn.

    (2005)
  • B.J. Park et al.

    Polymer-coated magnetic carbonyl iron microparticles and their magnetorheological characteristics

    Korean J. Chem. Eng.

    (2010)
  • Cited by (32)

    • Chemically enabling CoFe<inf>2</inf>O<inf>4</inf> for magnetostrictive strain sensing applications at lower magnetic fields: Effect of Zn substitution

      2021, Materials Science and Engineering: B
      Citation Excerpt :

      The higher magnetization associated with the Zn-substituted samples can be described based on the site preference and the nature of the Zn2+ ion. The Zn2+ is a non-magnetic transition metal ion with a strong preference for the tetrahedral site (A-site) for almost all of the known ferrites [41–47]. In our present system, the substitution of Zn2+ for either Co2+ or Fe3+ in cobalt ferrite enhances the overall magnetization of the material due to the A-site magnetic dilution [18].

    • Additive effect of rod-like magnetite/sepiolite composite particles on magnetorheology

      2021, Journal of Industrial and Engineering Chemistry
      Citation Excerpt :

      In addition, there have been various studies on MRFs regarding particles with different morphologies, including irregular, spherical, rod-like, octahedral, coral-like and other shapes. These studies showed that the MR properties are highly dependent on the magnetic properties, particle morphology, particle size, and particle size distribution [35–44]. Meanwhile, sepiolite is a kind of clay with rod-like shape and a relatively low density.

    • Effect of fuel and fuel to oxidizer ratio in solution combustion synthesis of nanoceramic powders: MgO, CaO and ZnO

      2020, Solid State Sciences
      Citation Excerpt :

      On the other hand, the solution combustion synthesis (SCS) is a simple technique, where rapid production of ceramic materials is possible at a very low cost, which will save valuable time and energy. More importantly, this method can be employed to synthesize homogeneous, high purity and/or uniformly doped nano-crystalline ceramic powder materials [1,13–31]. As it is known, the powder characteristics, such as crystallite size, surface area and phase purity etc., are primarily decided by the enthalpy of the combustion reaction (ΔHr), which can be observed as the variation in flame temperature generated during the combustion reaction.

    View all citing articles on Scopus
    View full text