Tailoring magnetic and dielectric properties of rubber ferrite composites containing mixed ferrites

Influence of Ca substitution on structural, magnetic and dielectric properties of Ba3Co2-xCaxFe24O41(where x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0), prepared by Sol-Gel auto-combustion method, has been investigated in present studies. The obtained powder was sintered at 950 oC for 4 hrs. in the static air atmosphere. Structural analysis of Ca-doped Ba3Co2-xCaxFe24O41powders revealed pure Z-type hexaferrite phase at low temperature. The frequency dependent dielectric constant (Єʹ) and magnetic properties such as remanent magnetization (Mr), saturation magnetization (Ms) and coercivity (Hc) were studied. It is observed that coercivity increased gradually with increase in calcium content. The real dielectric constant (Єʹ) and dielectric loss tangent (tan δ) were studied in the frequency range of 20Hz to 2MHz. The dielectric parameters for all samples show normal dielectric behavior as observed in hexaferrites. Contents of Paper

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Novel Polyimide/Copper-Nickel Ferrite Composites with Tunable Magnetic and Dielectric Properties

Polymers ◽

10.3390/polym13101646 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1646

Author(s):

Corneliu Hamciuc ◽

Mihai Asandulesa ◽

Elena Hamciuc ◽

Tiberiu Roman ◽

Marius Andrei Olariu ◽

...

Keyword(s):

Dielectric Properties ◽

Nickel Ferrite ◽

Scanning Calorimetry ◽

X Ray ◽

Broadband Dielectric Spectroscopy ◽

Copper Nickel ◽

Low Dielectric ◽

Magnetic Remanence ◽

Polyimide Matrix ◽

Ferrite Composites

Heat-resistant magnetic polymer composites were prepared by incorporating cerium-doped copper-nickel ferrite particles, having the general formula Ni1-xCuxFe1.92Ce0.08O4 (x: 0.0, 0.3, 0.6, 1.0), into a polyimide matrix. The effects of particle type and concentration on the thermal, magnetic, and electrical properties of the resulting composites were investigated. The samples were characterized by FTIR, scanning electron microscopy, X-ray diffractometry, thermogravimetric analysis, differential scanning calorimetry, vibrating sample magnetometer, and broadband dielectric spectroscopy. The composites exhibited high thermal stability, having initial decomposition temperatures between 495 and 509 °C. Saturation magnetization (Ms), magnetic remanence (Mr), and coercivity (Hc) were found in range of 2.37–10.90 emu g−1, 0.45–2.84 emu g−1, and 32–244 Oe, respectively. The study of dielectric properties revealed dielectric constant values of 3.0–4.3 and low dielectric losses of 0.016–0.197 at room temperature and a frequency of 1 Hz.

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Magnetic and Dielectric Properties of a Metal/ Cr2O3/Cr2O3-x/Cr2O3/Semiconductor Capacitor Using Magneto-Electric Materials

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.350.221 ◽

2007 ◽

Vol 350 ◽

pp. 221-224

Author(s):

Takeshi Yokota ◽

Takaaki Kuribayashi ◽

Takeshi Shundo ◽

Keita Hattori ◽

Yasutoshi Sakakibara ◽

...

Keyword(s):

Dielectric Properties ◽

Magnetic Moment ◽

Floating Gate ◽

Single System ◽

Insulating Layer ◽

Ferromagnetic Properties ◽

Capacitance Voltage ◽

Magnetic And Dielectric Properties ◽

Mis Capacitor ◽

Electric Materials

We investigated the magnetic and dielectric properties of a metal (Pt)/insulator (Cr2O3)/semiconductor (Si) (MIS) capacitor composed of magneto-electric (ME) materials. The capacitor has anti-ferromagnetic properties and a very small electrically induced magnetic moment. It also shows capacitance-voltage (C-V) properties typical of a Si-MIS capacitor without any hysteresis. By inserting a thin Cr2O3-x layer, the C-V curve has a hysteresis window with a clockwise trace, which indicates that electrons have been injected into the Cr2O3-x layer. These results indicate that this MIS capacitor contains a floating gate and an ME insulating layer in a single system.

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