Multiple sintering of MnZn ferrites in controlled atmosphere

  • M. I. Alam
  • N. R. Nair
  • T. V. Ramamurti


A series of experiments were conducted on multilayer sintering of MnZn ferrite cores in a production type furnace. The cup cores were stacked one over the other, up to ten layers and each loading of the furnace had 3000 cup cores 18×11mm in size. All the electrical characteristics such as permeability, resistivity, eddy current and hysterisis loss, disaccommodation and temperature factor were measured. There was no significant difference between layers in these factors. Experimental data supporting these observations are presented. Production runs were undertaken and the experimental findings were confirmed. It is suggested that the soaking time of one and a half hr and slower cooling rate has helped to attain equilibrium conditions allowing the gases to permeate to all the layers. The variation in electrical characteristics that are evident appears to be due to the inherent limitations in process control.


Ferrite Rabie Temperature Factor Slow Cool Rate Eddy Current Loss 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Slick, P. L. and Besseches, H.,IEEE Trans. Mag-2, 603 (1966).Google Scholar
  2. 2.
    Morineau, R. and Paulus, M.,Phys. Stat. Sol. (a) 20 373 (1973).CrossRefGoogle Scholar
  3. 3.
    Morineau, R. and Paulus, M., Sept. 1975,IEEE Trans. Mag-11, No. 5 1312.Google Scholar
  4. 4.
    Nair, N. R., Khanduja, R. S. and Ramamurti, T. V.,Proc. Symp. Mat. Sci. Res. D.A.E.1 400 (1970).Google Scholar
  5. 5.
    Alam, M. I., Nair, N. R., Sharma, C. D. and Ramamurti, T. V.,Res. Ind. 19 139 (1974).Google Scholar
  6. 6.
    Mossman, P.,Magnetic Materials and their Applications. Conf. Pub. 33. (Institute of Electrical Engineers, London) pp. 164 (1967).Google Scholar
  7. 7.
    Blank, J. M.,J. Appl. Phys. 36 1022 (1965).CrossRefGoogle Scholar
  8. 8.
    Alam, M. I., Shambhavi De vi Rao, Ramadevi Ramchandran, Nair, N. R. and Ramamurti T. V.,Proc. Indian Acad. Sci. A82 (1975).Google Scholar
  9. 9.
    Chol, G., Damay, F., Auradon, J. P., and Strivens, H. A.,Elec. Commun. 43 3 263 (1968)Google Scholar

Copyright information

© Indian Academy of Sciences 1977

Authors and Affiliations

  • M. I. Alam
    • 1
  • N. R. Nair
    • 1
  • T. V. Ramamurti
    • 2
  1. 1.Central Electronics LimitedNew Delhi
  2. 2.New Delhi

Personalised recommendations