Effects of Bi 2 O 3 -Nb 2 O 5 additives on microstructure and magnetic properties of low-temperature-fired NiCuZn ferrite ceramics

Microstructure, magnetic, and power loss characteristics of low‐sintered NiCuZn ferrites with La2O3‐Bi2O3 additives

“…This opposite variation trend was in accordance with the Snoek's law 31 . As is known, the complex permeability of NiCuZn ferrites is determined by two magnetization mechanisms: domain spin rotation and domain wall motion 32,33 . However, the average grain size of the samples in this experiment was only about 1 μm.…”

“…31 As is known, the complex permeability of NiCuZn ferrites is determined by two magnetization mechanisms: domain spin rotation and domain wall motion . 32,33 However, the average grain size of the samples in this experiment was only about 1 μm. And according to Figure 5, all grain sizes are smaller than the single domain critical size (3 μm) of NiZn ferrites.…”

“…: $$$$\begin{equation}\mu \approx 1 + \ {\chi _{{\mathrm{spin}}}} = \ 1 + \frac{{4\pi {M_s}}}{{{H_d} + {H_A}}},\end{equation}$$$$where $${M_s}$$ is the saturation magnetization, $${H_d}$$ is the demagnetization field, and $${H_A}$$ is the magnet anisotropic field of the ferrite, respectively. The reduction of porosity helps to decrease the demagnetization field, and the improvement of densification is beneficial to the enhancement of permeability 33 . With the increase of La 2 O 3 content, the relative density increased and the porosity decreased.…”

Synergistic Structural Engineering of Tunnel‐Type Polyantimonic Acid Enables Dual‐Boosted Volumetric and Areal Lithium Energy Storage

“…This can be further corroborated by the appreciable theoretical density (5.66 g cm -3 ) in the case of Mn 2+ -fully-occupied PAA, which is much higher than that of pristine PAA (4.29 g cm -3 ), and even than most of commonly investigated electrode materials in LIBs, such as graphite (2.26 g cm -3 ), Li 4 Ti 5 O 12 (3.42 g cm -3 ), Si (2.33 g cm -3 ), Fe 2 O 3 (5.26 g cm -3 ), MnO (5.43 g cm -3 ) and Nb 2 O 5 (4.47 g cm -3 ). [18][19][20][21][22][23] Such a considerable theoretical density of Mn-substituted PAA makes it promising in acquiring high tap density so as to probably build relatively thinner electrodes under identical high mass loadings, in turn contributing to high areal and volumetric capacities.…”

Магнитные и радиопоглощающие свойства поликристаллического феррита-шпинели Li-=SUB=-0.33-=/SUB=-Fe-=SUB=-2.29-=/SUB=-Zn-=SUB=-0.21-=/SUB=-Mn-=SUB=-0.17-=/SUB=-0-=SUB=-4-=/SUB=-

“…Технологическая схема получения в работе ферритовшпинелей Li 0.33 Fe 2.29 Zn 0.21 Mn 0.17 O 4 методом керамической технологии. 1100 • C. Обычно температура спекания литий-цинковых ферритов-шпинелей выше 950 • C[16], но на ее снижение могут влиять такие факторы как атмосфера синтеза[17], тип и концентрация интенсифицирующих спекание добавок[18][19][20][21][22], вид и количество замещающих катионов[23][24][25]. В связи с этим целесообразны попытки провести синтез при такой относительно низкой температуре как 950 • C. Образцы были изготовлены в форме колец с внешним и внутренним диаметрами 16.0 и 7.0 mm соответственно и высотой h = 5.0−6.0 mm.…”