Influence of Co content on structural and magnetic properties of CoxFe84−xNb7B9 alloys

Kane, S. N.; Gupta, Ajay; Sarabhai, S.D; Kraus, L.

doi:10.1016/s0304-8853(02)00848-x

Cited by 10 publications

(6 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although several studies have been devoted to Nb-containing HITPERM [19,[21][22][23][24][25][26][27][28][29] and Co-FINEMET alloys [10][11][12][13][14][15] separately, a detailed comparative study showing the common mechanisms of the nanocrystallization phenomenon of the α-Fe, Co(Si) phase is missing. In this work, this study is performed in terms of their microstructure and magnetic properties.…”

Section: Introductionmentioning

confidence: 99%

On the effects of partial substitution of Co for Fe in FINEMET and Nb-containing HITPERM alloys

Blázquez

Borrego

Conde

et al. 2003

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

A comparative study of the effects of partial substitution of Co for Fe on thermal stability, crystallization and magnetic properties of Co-containing FINEMET and HITPERM alloys series is presented. The difference in metalloid and Nb content between the two alloy series and the presence of Si in the nanocrystals in the case of FINEMET alloys appear as key parameters. A recrystallization process involving the α-Fe type phase in nanocrystalline alloys of both series is evident from thermomagnetic results as a significant decrease in magnetization at the second crystallization stage.

show abstract

Section: Introductionmentioning

confidence: 99%

On the effects of partial substitution of Co for Fe in FINEMET and Nb-containing HITPERM alloys

Blázquez

Borrego

Conde

et al. 2003

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…It may be noted that, in order to get best fitting in crystalline state of the alloy, an additional doublet corresponding to Nb-rich non magnetic phase was also included in the fitting model for alloys annealed at and above 773 K. Evidence of the formation of such non magnetic niobate phase was also observed after annealing at 773 K in earlier studies in the nanocrystallisation stage. 36 The fitting of the Mössbauer spectra after annealing at 773 K suggests that nearly 46% of Fe resides in the amorphous state. The presence of the hyperfine field components of 34.5 6 0.1 T shows the presence of bcc-FeCo nanocrystalline phase.…”

Section: Mö Ssbauer Measurementsmentioning

confidence: 98%

“…Decrease of quadrupole splitting with annealing temperature indicated possible ordering of the Nb-rich non-magnetic phase which can be attributed to (FeCo) 3 Nb phase. 36 Furthermore, the A23 parameter (the area ratio of the second and third lines of the Mössbauer spectra) gives information about the orientation of the magnetic moment. It was found that the A23 parameter for as-quenched alloy is 2.6 6 0.1, which suggests that orientation of spins is not random rather they have some preference for the in-plane orientation.…”

Section: Mö Ssbauer Measurementsmentioning

confidence: 99%

Influence of isochronal annealing on the microstructure and magnetic properties of Cu-free HITPERM Fe40.5Co40.5Nb7B12 alloy

Gupta

Ganguli

Gupta

et al. 2012

Journal of Applied Physics

View full text Add to dashboard Cite

Systematic study of the effect of isochronal annealing on the structure and magnetic properties of Cu-free HITPERM alloy (Fe40.5Co40.5Nb7B12) is described herein. Mo¨ssbauer spectroscopy (MS) and anomalous x-ray diffraction (XRD) measurement at Fe K-edge (7.112 keV) jointly provide clear evidence for the presence of atomically ordered a0-FeCo (B2 structure) phase as a nanocrystalline ferromagnetic phase. Being a short range order probe, Mo¨ssbauer spectroscopy also confirms the development of an additional non-magnetic Nb-rich phase in the nanocrystalline specimens (annealed above 723 K) with simultaneous lowering of the volume fraction of ferromagnetic phases. The fraction of Fe atoms in the non-magnetic phase is rv15% upon annealing at 773 K for 1 h, which increases gradually and reaches to as high as rv19% after annealing at 923 K. This phase was not detected by XRD and transmission electron microscopy (TEM) measurements, which may be attributed to tiny crystallite size and/or high degree of disorder. In the second stage of crystallization, i.e., above 923 K, the alloy becomes fully crystalline and a stable, hard magnetic fcc-(FeCo)23B6 type phase was observed as a main boride phase along with soft magnetic a0-FeCo phase and Nb rich non-magnetic phase. Thermo magnetic measurement evidenced re-crystallization process as a considerable decrease in magnetization at the second transformation stage. Simultaneous lowering of the volume fraction of magnetic phases with the formation of non-magnetic phase provides convincing origin for the decrease in magnetization at the second crystallization stag

show abstract

“…[9][10][11][12] As shown in the literature, the magnetic properties of amorphous alloys depend strongly on the annealing temperature. [13][14][15][16] During the earlier sample production process, free volumes are created; annealing the samples at low temperatures leads to the diffusion of these free volumes to the surface of the material. Thus, the soft magnetic properties of these alloys can be improved Materiali in tehnologije / Materials and technology 51 (2017) 1, 157-162 through the relaxation of internal stress, by annealing them at less than the crystallization temperature.…”

Section: Introductionmentioning

confidence: 99%

The influence of an isothermal annealing process on the structure and magnetic properties of the bulk amorphous alloy FeCoBYMo

Pietrusiewicz¹,

Nabiałek²,

Olszewski³

et al. 2017

Mater. Tehnol.

View full text Add to dashboard Cite

This paper presents the results of research into a bulk amorphous alloy based on Fe. Samples with the composition Fe61Co10Y8Mo1B20 were prepared in the form of plates using an injection-casting method. The samples were then subjected to an isothermal annealing process (at less than the crystallization temperature) of 700 K for 1 h and 770 K for 3.5 h The structures of the samples were investigated, both in the state after solidification and following the heat treatment, using X-ray diffraction (XRD) and Mössbauer spectroscopy. The results confirmed that the samples, both after solidification and after annealing, were amorphous. Magnetic measurements were carried out using a vibrating-sample magnetometer (VSM) with magnetic fields of up to 2 T. Based on these measurements, the effect of the isothermal annealing process on the magnetic properties was defined, including the saturation magnetization μ0Ms and coercive field Hc. Using the Kronmüller theory, the initial magnetization curves were analysed in the area of approach to ferromagnetic saturation. On the basis of this theory, the quantity and quality of the structural defects were defined; these defects play a critical role in the magnetization process in high magnetic fields. Following this study, the sample annealed at 770 K for 1 h was found to feature a relatively low coercive field and the higher value of magnetization saturation. Linear defects, the so-called quasidislocational dipoles, played the leading role in the process of magnetization of the test samples. Keywords: bulk amorphous alloys, structure, soft magnetic properties, defectŝ lanek predstavlja rezultate raziskave masivne amorfne zlitine na osnovi Fe. Vzorci s sestavo Fe61Co10Y8Mo1B20 so bili pripravljeni v obliki plo{~, s pomo~jo tla~nega litja. Vzorci so bili izotermno`arjeni 1 h (pri temperaturi ni`ji od temperature kristalizacije) na 700 K in 3,5 h na 770 K. Preiskana je bila struktura vzorcev, v stanju po strjevanju in po toplotni obdelavi. Uporabljena je bila rentgenska difrakcija (XRD) in Mössbauerjeva spektroskopija. Rezultati so potrdili, da so bili vzorci po strjevanju in po`arjenju v amorfnem stanju. Magnetne meritve so bile izvedene s pomo~jo magnetometra z vibriranjem vzorca (VSM) v magnetnih poljih jakosti do 2 T. Na osnovi meritev je bil dolo~en vpliv izotermnega`arjenja na magnetne lastnosti, vklju~no z nasi~eno magnetizacijo μ0Ms in koercitivnim poljem Hc. Z uporabo Kronmüllerjeve teorije so bile analizirane za~etne krivulje magnetizacije blizu podro~ja feromagnetnega nasi~enja. Na osnovi te teorije je bila dolo~ena koli~ina in kakovost strukturnih napak; te napake igrajo klju~no vlogo pri procesu magnetizacije v mo~nih magnetnih poljih. Na podlagi te {tudije je bilo ugotovljeno, da vzorci`arjeni 1 h ka`ejo relativno {ibko koercitivno polje in visoko vrednost nasi~ene magnetizacije. Linearne napake, imenovane kvazi-dislokacijski dipoli, igrajo vodilno vlogo pri procesu magnetizacije preizku{anih vzorcev. Klju~ne besede: masivne amorfne zlitine, struktura, mehko magnetne lastn...

show abstract

Influence of Co content on structural and magnetic properties of CoxFe84−xNb7B9 alloys

Cited by 10 publications

References 8 publications

On the effects of partial substitution of Co for Fe in FINEMET and Nb-containing HITPERM alloys

On the effects of partial substitution of Co for Fe in FINEMET and Nb-containing HITPERM alloys

Influence of isochronal annealing on the microstructure and magnetic properties of Cu-free HITPERM Fe40.5Co40.5Nb7B12 alloy

The influence of an isothermal annealing process on the structure and magnetic properties of the bulk amorphous alloy FeCoBYMo

Contact Info

Product

Resources

About