Characterization of Y-type hexaferrite Ba&lt;inf&gt;2&lt;/inf&gt;Mg&lt;inf&gt;2&lt;/inf&gt;Fe&lt;inf&gt;12&lt;/inf&gt;O&lt;inf&gt;22&lt;/inf&gt; powders

Georgieva, Borislava; Krezhov, K.; Kolev, Svetoslav; Ghelev, Chavdar; Kovacheva, Daniela; Fábián, Margit; Sváb, E.; Koutzarova, T.

doi:10.1109/isse.2017.8000885

Cited by 3 publications

(8 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In our previous studies [10,11] we showed that in a Ba2Mg2Fe12O22 powder material synthesized by sonochemical co-precipitation the magnetic phase transition from ferromagnetic-to-spiral spin order occurs at 196 K at a magnetic field of 100 Oe.…”

Section: Introductionmentioning

confidence: 92%

Study of the Properties of Co-Substituted Ba2Mg2Fe12O22 Hexaferrites

Koutzarova

Georgieva

Kolev

et al. 2018

Proceedings of the 3rd International Electronic Conference on Materials Sciences

Self Cite

View full text Add to dashboard Cite

We present results from a study on the influence of the substitution of Mg 2+ cations in the Y-type Ba2Mg2Fe12O22 hexaferrite with magnetic cations, such as Co 2+ , on its structural and magnetic properties. The Ba2Mg0.4Co1.6Fe12O22 powder was synthesized by sonochemical co-precipitation method. The XRD pattern of the powders showed the characteristic peaks corresponding to the Ytype hexaferrite structure as a main phase and some CoFe2O4 impurity (< 2%) as a second phase. This result was also confirmed by Mössbauer spectroscopy measurements. The magnetization values at 50 kOe were 30 emu/g at 4.2 K and 26.6 emu/g at 300 K, respectively. The ZFC and FC magnetization curves were measured at magnetic fields of 50 Oe, 100 Oe and 500 Oe, which revealed a magnetic phase transition around 200 K from ferrimagnetic-to-helical spin order. This is considered as a precondition for the material to exhibit multiferroic properties.

show abstract

Section: Introductionmentioning

confidence: 92%

Study of the Properties of Co-Substituted Ba2Mg2Fe12O22 Hexaferrites

Koutzarova

Georgieva

Kolev

et al. 2018

Proceedings of the 3rd International Electronic Conference on Materials Sciences

Self Cite

View full text Add to dashboard Cite

show abstract

“…SEM image of Ba 2 Mg 2 Fe 12 O 22 powders prepared via (a) autocombustion and (b) ultrasonically assisted co-precipitation . (a) Reprinted with permission from ref .…”

Section: Synthesis Techniques Of Y-type Hexaferritesmentioning

confidence: 99%

“…The precursors produced by these co-precipitation methods are synthesized at 1170 °C. We described in detail such a procedure for the synthesis of different Y-type hexaferrites. − We also reported , a comparative investigation on this synthesis method’s effect on the microstructural and magnetic parameters of Ba 2 Mg 2 Fe 12 O 22 powder materials and found that the ultrasonically assisted co-precipitation produced particles with a practically perfect hexagonal shape compared with the particles obtained by sol–gel autocombustion (Figure b). The average thickness of the Ba 2 Mg 2 Fe 12 O 22 particles was 380 nm.…”

Section: Synthesis Techniques Of Y-type Hexaferritesmentioning

confidence: 99%

Phase Transitions in Magneto-Electric Hexaferrites

et al. 2022

Self Cite

View full text Add to dashboard Cite

Hexaferrites have long been the object of extensive studies because of their great possibility for applications�permanent magnets, highdensity recording media, microwave devices, in biomedicine, to name but a few. Lately, many researchers' efforts have been focused on the existence of the magneto-electric effect in some hexaferrite systems and the appealing possibility of them being used as single-phase multiferroic and magnetoelectric materials. As indicated by theoretical analyses, the origin of the large magneto-electric effect can be sought in the strong interaction between the magnetization and the electric polarization that coexist in insulators with noncollinear magnetic structures. The hexaferrites' magnetic structure and, particularly, the specific magnetic spin ordering are the key factors in observing magneto-electric phases in hexaferrites. Some of these phases are metastable, which hampers their direct practical use. However, as the hexaferrites' phase diagrams reveal, chemical doping can be used to prepare a number of noncollinear stable magnetic phases. Since the magneto-electric effect has to do with the magnetic moments ordering, it seems only logical that one should study the cation substitutions' influence on the magnetic phase transition temperature. In this paper, we summarize recent examples of advances in the exploration of magnetic phase transitions in Y-type hexaferrites. In particular, the effect is emphasized by substituting in Y-type hexaferrites the nonmagnetic Me 2+ cations with magnetic ones and of the magnetic Fe 3+ cations with nonmagnetic ones on their magnetic properties and magnetic phase transitions. The work deals with the structural properties of and the magnetic phase transitions in a specific Y-type hexaferrite, namely, Ba(Sr) 2 Me 2 Fe 12 O 22 .

show abstract

“…In our previous studies [25,26], we showed that in a Ba 2 Mg 2 Fe 12 O 22 powder material synthesized by sonochemical co-precipitation, the magnetic phase transition from ferromagnetic-to-spiral spin order occurs at 196 K at a magnetic field of 100 Oe.…”

Section: Introductionmentioning

confidence: 99%

“…In some of our earlier works, we have studied in detail the effect of the preparation technique on the microstructural and magnetic properties of Ba 2 Mg 2 Fe 12 O 22 powders [25,26]. We found that using sonochemical co-precipitation results in the formation of Ba 2 Mg 2 Fe 12 O 22 particles with perfect hexagonal shape, as opposed to the case of performing auto-combustion; moreover, better magnetic properties were achieved.…”

Section: Introductionmentioning

confidence: 99%

Study of the Structural and Magnetic Properties of Co-Substituted Ba2Mg2Fe12O22 Hexaferrites Synthesized by Sonochemical Co-Precipitation

et al. 2019

Self Cite

View full text Add to dashboard Cite

Ba2Mg0.4Co1.6Fe12O22 was prepared in powder form by sonochemical co-precipitation and examined by X-ray diffraction, Mössbauer spectroscopy and magnetization measurements. Careful XRD data analyses revealed the Y-type hexaferrite structure as an almost pure phase with a very small amount of CoFe2O4 as an impurity phase (about 1.4%). No substantial changes were observed in the unit cell parameters of Ba2Mg0.4Co1.6Fe12O22 in comparison with the unsubstituted compound. The Mössbauer parameters for Ba2Mg0.4Co1.6Fe12O22 were close to those previously found (within the limits of uncertainty) for undoped Ba2Mg2Fe12O22. Isomer shifts (0.27–0.38 mm/s) typical for high-spin Fe3+ in various environments were evaluated and no ferrous Fe2+ form was observed. However, despite the indicated lack of changes in the iron oxidation state, the cationic substitution resulted in a significant increase in the magnetization and in a modification of the thermomagnetic curves. The magnetization values at 50 kOe were 34.5 emu/g at 4.2 K and 30.5 emu/g at 300 K. The zero-field-cooled (ZFC) and field-cooled (FC) magnetization curves were measured in magnetic fields of 50 Oe, 100 Oe, 500 Oe and 1000 Oe, and revealed the presence of two magnetic phase transitions. Both transitions are shifted to higher temperatures compared to the undoped compound, while the ferrimagnetic arrangement at room temperature is transformed to a helical spin order at about 195 K, which is considered to be a prerequisite for the material to exhibit multiferroic properties.

show abstract

Characterization of Y-type hexaferrite Ba<inf>2</inf>Mg<inf>2</inf>Fe<inf>12</inf>O<inf>22</inf> powders

Cited by 3 publications

References 8 publications

<strong>Study of the Properties of Co-Substituted Ba<sub>2</sub>Mg<sub>2</sub>Fe<sub>12</sub>O<sub>22</sub> Hexaferrites</strong>

<strong>Study of the Properties of Co-Substituted Ba<sub>2</sub>Mg<sub>2</sub>Fe<sub>12</sub>O<sub>22</sub> Hexaferrites</strong>

Phase Transitions in Magneto-Electric Hexaferrites

Study of the Structural and Magnetic Properties of Co-Substituted Ba2Mg2Fe12O22 Hexaferrites Synthesized by Sonochemical Co-Precipitation

Contact Info

Product

Resources

About