Induced magnetic anisotropy features in FeCrSiBNbCu nanocrystalline alloy: Role of stress distribution proven by direct X-ray measurements

Abstract

a b s t r a c tFe 73.5Àx Cr x Si 13.5 B 9 Nb 3 Cu 1 (x = 1, 2, and 3) amorphous ribbons were prepared by single roller rapid quenching technique. Both conventional and stress annealing at 520 °C for 2 h at the value of the specific load of 150 MPa resulted in the formation of a nanocrystalline structure with average grain size about 13 nm. No significant differences in crystallite size were observed for all samples under consideration. The crystallite orientations were practically isotropic indicating no texture in the samples of all types. For all conventional ly annealed ribbons a longitudinal effective magnetic anisotropy with an easy magnetization axis parallel to the ribbon axis was observed. For all stress anneale d ribbons a transverse induced magnetic anisotropy with the anisotropy constant value of about 1800 ± 50 J/m 3 was evident.Induced magnetic anisotropy features in FeCrSiBNbCu nanocrystalli ne alloy, namely an importance of the stress distribution was proven by direct X-ray measurements. A very good correlation between the induced magnetic anisotropy constant values and anisotropic stress distribution was observed.

Stress-Annealing Induced Anisotropy in FeCrCuNbSiB Nanocrystalline Wires

“…Since the load is still applied in the process of cooling, this microstructure can be reserved in the stress-annealed samples. This induced anisotropy had been observed in minor substitution of Fe for Cr (1-5 at.% Cr) Finemet alloys [4,5], and it was reported that the minor substitution of Fe for Cr can improves the thermal stability of the alloy [4]. In this work, the stress-annealing induced anisotropy of Cr-doped (up to 7 at.% Cr) Finemet nanocrystalline wires is studied, especially, an anomalous stress-dependent induced anisotropy is reported.…”

Research Progress of Stress-Induced Magnetic Anisotropy in Fe-Based Amorphous and Nanocrystalline Alloys

“…Quite recently, Gavrilovic et al [35] identified multiple crystalline phases in a FeCuNbSiB sample which was heat treated at 1123K for 24h. Kurlyandskaya et al [10] used the XRD to analyze the texture features in soft nanocrystalline FeCrSiBNbCu alloys and for different compositions it was shown that stress annealing typically results in no texturing [36]. Figure 4 shows the XRD patterns of an FeCuNbSiB sample annealed at 973K studied by Gavrilovic et al [37] which revealed the different phases which become present after the sample has been subjected to the annealing process.…”

“…Some of the methods which have been used to tailor these properties are annealing which is microstructural modification process [7] and addition of other alloying elements such as Co, Ni, Mo, Zr, Ta, Cr. Quite recently, Cr containing nanocrystalline have attracted some interest [8] [9] due to the positive effect chromium has on soft magnetic properties in addition to corrosion resistance and increase in thermal stability [10] whilst showing high values of stress induced magnetic anisotropy constant. Induced anisotropy was shown to be a special way in tailoring magnetic permeability by stress or field annealing [11] [12] of which stress annealing was found to induce the highest anisotropy in soft nanocrystalline alloys compared.…”

Влияние кристаллизующего отжига под нагрузкой на магнитные свойства и структуру магнитомягкого сплава FeSiNbCuB, легированного хромом

“…Термомеханическая обработка (отжиг и охлаждение под растягивающей нагрузкой -ТМехО) приводи-ла во всех образцах указанных составов к наведе-нию поперечной магнитной анизотропии (типа " жесткая ось"), после обработки петли гистерезиса из верти-кальных становились наклонными и оставались линей-ными [6]. В работе [7] на нанокристаллических образ-цах Fe 73.5−X Cr X Si 13.5 B 9 Nb 3 Cu 1 (X = 0−4) наблюдалась доменная структура после отжига под растягивающей нагрузкой и без нее.…”

“…В работе [5] было показано на образцах этих же составов, что добавка хрома за счет железа приводит к уменьшению максимальной намагниченности (в поле до 8 kA/m) с 1.25 до 0.88 T при изменении содержания хрома от 0 до 5% соответственно. При содержании хрома 1−3% коэрцитивная сила оставалась в пределах 2−4 A/m и возрастала до 23 A/m при 5% хрома.Термомеханическая обработка (отжиг и охлаждение под растягивающей нагрузкой -ТМехО) приводи-ла во всех образцах указанных составов к наведе-нию поперечной магнитной анизотропии (типа " жесткая ось"), после обработки петли гистерезиса из верти-кальных становились наклонными и оставались линей-ными [6]. В работе [7] на нанокристаллических образ-цах Fe 73.5−X Cr X Si 13.5 B 9 Nb 3 Cu 1 (X = 0−4) наблюдалась доменная структура после отжига под растягивающей нагрузкой и без нее.…”