Copper-cobalt ferrites with general chemical formula CuxCo1-xFe2O4 (with x = 0.0, 0.4, 0.6 & 1.0) were prepared by ceramic method. The solid state reaction was confirmed by XRD patterns. DC conductivity was measured by two probe method. Electrical resistivity is found to increase on lowering of sintering temperature and time. At x = 1.0, the conduction is mainly due to hopping of electrons leading to n-type conductivity while at x = 0.0, conduction is due to holes leading to P-type conductivity. The lowest conduction at x = 0.4 is attributed to the electron hole compensation. SEM micrographs were obtained from JEOL scanning electron microscope. The micrographs reveal that an average grain size increases with sintering temperature and time as a result of decrease in porosity. This leads to the decrease in resistivity with sintering temperature and time. One of the factors for higher conductivity in ferrites is an increase in average grain size and decrease in pore concentration during the heat treatment.
2. Lagarkov, A. L., V. N. Kisel, and U. N. semenenko, "Wideangle absorption by use of a metamaterial plate," Progress In Electromagnetics Research Letters, Vol. 1, 35-44, 2008.
doi:10.2528/PIERL07111809
3. Kumar, A. and S. Sharma, "Measurement of dielectric constant and loss factoe of the dielectric material at microwave frequencies," Progress In Electromagnetics Research, Vol. 69, 47-54, 2007.
doi:10.2528/PIER06111204
4. Kkalaj-Amirhosseini, M., "Microwave filters using waveguides filled by multilayer dielectric," Progress In Electromagnetics Research, Vol. 66, 105-110, 2006.
doi:10.2528/PIER06102502
5. Soliman, E. A. and G. A. E. Vandenbosch, "Greens functions of filament sources embedded in stratified dielectric media," Progress In Electromagnetics Research, Vol. 62, 21-40, 2006.
doi:10.2528/PIER06022401
6. Nikellis, K., N. Uzunoglu, Y Koutsoyannopoulos, and S. Bantas, "Full-wave modeling of stripline structures in multilayer dielctrics," Progress In Electromagnetics Research, Vol. 57, 253-264, 2006.
doi:10.2528/PIER05071302
7. Saed, M. and R. Y. Yadla, "Microstrip-fed low profile and compact dielectric resonator antennas," Progress In Electromagnetics Research, Vol. 56, 151-162, 2006.
doi:10.2528/PIER05041401
8. Fu, Y. P., K. Y. Pan, and C. H. Lin, "Ni-Cu-Zn ferrite powder from steel pickled liquor and electroplating waste solutions," Mater. Lett., Vol. 57, 291-296, 2002.
doi:10.1016/S0167-577X(02)00780-2
9. Singhal, S., J. Singh, S. K. Barthwal, and K. Chandra, "Preparation and characterization of nanosized nickelsubstituted cobalt ferrite," J. Solid. State. Chem., Vol. 178, 3183-3189, 2005.
doi:10.1016/j.jssc.2005.07.020
10. Afrang, S. and B. Y. Majlis, "Small size KA-band distributed MEMS phase shifters using inductors," Progress In Electromagnetics Research B, Vol. 1, 95-113, 2008.
doi:10.2528/PIERB07101903
11. Wongkasem, N. and A. Akyurtlu, "Noel broadband tetrahertz negative refractive index metamaterials: Analysis and experiment," Progress In Electromagnetics Research, Vol. 64, 205-218, 2006.
doi:10.2528/PIER06071104
12. Wongkasem, N., A. Akyurtlu, and K. A. Marx, "Group theory based design of isotropic negative refractive index metamaterials," Progress In Electromagnetics Research, Vol. 63, 295-310, 2006.
doi:10.2528/PIER06062103
13. Rahman, I. Z. and T. T. Ahmed, "A study on copper substituted chemically processed Ni-Zn-Cu ferrites," J. Magn. Magn. Mater., Vol. 290, 290-291, 2005.
doi:10.1016/j.jmmm.2004.11.211
14. Tosyulu, O. S., J. Gowri Krishna, and J. Sobhanandri, "A method for the evaluation of dielectric parameters of solids at microwave frequencies," J. Phys. E: Scientific Instruments, Vol. 59, 323-327, 1982.
15. He, X., Z. Tang, B. Zhang, and Y. Wu, "A new deem bedding method in permittivity measurement of ferroelectric thin film material," Progress In Electromagnetics Research Letters, Vol. 3, 1-8, 2008.
doi:10.2528/PIERL08011501
16. Chinnasamy, C. N., A. Narayanasamy, N. Ponpandian, K. CattopadhyayH. Gueralt, and J. M. Greneche, "Magnetic properties of nanostructured ferromagnetic zinc ferrites," J. Phys. Condens. Matter., Vol. 12, 7795-7799, 2000.
doi:10.1088/0953-8984/12/35/314
17. Nathani, H., S. Gubbala, and R. D. K. Misra, "Magnetic behaviour of nanocrystalline nickel ferrite part I: The effect of surface roughness," Mater. Sci. Engg., Vol. 121(B), 291-296, 2005.
18. Sivakumar, N., A. Narayanasamy, and N. Ponpandian, "Grain size effect on the dielectric behavior of nanostructured Ni0.5Zn0.5Fe2O4," J. Apply. Phy., Vol. 101, 084116-0841122, 2007.
doi:10.1063/1.2721379
19. Von Aulock, W. H., Hand Book of Microwave Ferrites, Academic Press, NY, 1965.
20. Ravinder, D. and B. Ravikumar, "A study on elastic behaviour of rare earth substituted Mn-Zn ferrites," Mater. Lett., Vol. 57, 4471-4473, 2003.
doi:10.1016/S0167-577X(03)00164-2
21. Krishnamurthy, K. R., Ph.D. Thesis, Indian Institute of Technology, Madras, India, 1975.
22. Pujar, R. B., S. N. Kulakarni, and B. K. Chougule, "Compositional, temperature and frequency dependence of initial permeability in Zr4+ substituted Mg-Zn ferrites," Mater. Sci. Lett., Vol. 15, 1605-1608, 1996.
23. Mishra, S., K. Kundu, K. C. Barick, D. Bahadur, and D. Chakravorty, "Prepration of nanocrystalline MnFe2O4 doping with Ti4+ions using solid state reaction route ," J. Magn. Magn. Mater., Vol. 307, 222-226, 2006.
doi:10.1016/j.jmmm.2006.04.005
24. Radhakrishana, S. and K. V. S. Badrinath, "Studies on the ferroelectric-parelectric transition of dicalcium lead propnate," J. Matt. Sci. Lett., Vol. 3, 575-577, 1984.
doi:10.1007/BF00719615
25. Verma, A., T. C. Goel, R. G. Mrndirratta, and P. Kishan, "Magnetic properties of nickel-zinc ferrites prepared by the citrate precursor method ," J. Magn. Magn. Mater., Vol. 208, 13-19, 2000.
doi:10.1016/S0304-8853(99)00585-5
26. Smit, J., Magnetic Properties of Materials, McGraw Hill Book Company, NY, 1971.
27. Koh Gue, J., New Phy., Vol. 24, 353-358, Korean Phy. Soc., 1984.
28. Hady, L. K. and A. A. Kishk, "Electromagnetic scattering from conducting circular cylinder coated by metamaterials and loaded with helical strips under oblique incidence," Progress In Electromagnetics Research B, Vol. 3, 189-206, 2008.
doi:10.2528/PIERB07121107