论文信息 - Ultralow dielectric constant nickel–zinc ferrites using microwave sintering

Ultralow dielectric constant nickel–zinc ferrites using microwave sintering

Ultralow dielectric constant values were measured on Ni-Zn ferrites prepared using Fe 2 O 3 as a starting material and sintered in a microwave field. Significant differences in microstructure, magnetic, and dielectric properties were observed between microwave-sintered Ni-Zn ferrites prepared using Fe 3 O 4 (T34) and those starting with Fe 2 O 3 (T23) ingredients. Higher magnetization values observed in T23 ferrite are attributed to large grain size, possibly containing abundant domain walls and the presence of fewer Fe 2 + ions. The ultralow dielectric constant values observed on T23 ferrites show that this procedure is highly suitable to prepare Ni-Zn ferrites for high-frequency switching applications.

R. Roy | C. Grimes | D. Agrawal | R. Peelamedu | Purushotham Yadoji

[1] V. Raja,et al. Optical properties of pure and doped PMMA-CO-P4VPNO polymer films , 2003 .

[2] R. Roy,et al. Microwave sintering of Ni–Zn ferrites: comparison with conventional sintering , 2003 .

[3] R. Roy,et al. Major phase transformations and magnetic property changes caused by electromagnetic fields at microwave frequencies , 2002 .

[4] Rustum Roy,et al. Definitive experimental evidence for Microwave Effects: radically new effects of separated E and H fields, such as decrystallization of oxides in seconds , 2002 .

[5] R. Roy,et al. Microwave-induced reaction sintering of NiAl2O4 , 2002 .

[6] R. Roy,et al. Anisothermal reaction synthesis of garnets, ferrites, and spinels in microwave field , 2001 .

[7] M. Hiti. Dielectric behaviour in Mg–Zn ferrites , 1999 .

[8] A. Abdeen. Dielectric behaviour in Ni–Zn ferrites , 1999 .

[9] K. J. Rao,et al. Use of microwaves for the synthesis and processing of materials , 1995 .

[10] T. Abraham. Economics of ceramic magnet , 1994 .

[11] K. Okazaki,et al. Effects of Porosity and Grain Size on the Magnetic Properties of NiZn Ferrite , 1977 .

[12] B. A. Calhoun,et al. Ferromagnetic materials , 1955 .

[13] C. G. Koops. On the Dispersion of Resistivity and Dielectric Constant of Some Semiconductors at Audiofrequencies , 1951 .