Experimental and calculated dependences of granular superconductor magnetic susceptibility on the superconducting volume fraction in regimes of shielding (ZFC), Meissner effect (FC) and remanence (REM) were determined. Fractional dependences were calculated with Braggeman's asymmetric theory and allowing for the shape of superconducting grains and the sample and the influence of grain sizes upon their polarizability under different magnetization conditions. A granular superconductor with intergranular links is calculated as a three-component system, where closed clusters are regarded as superconducting particles and the function of distribution of these particles, depending on the superconducting volume fraction, is introduced. The results of calculation agree well with the experimental data in t h e ZFC regime for all fractions f = &I, but in t h e a and REM regimes for f < 0.6. The calculation for the links region gives a qualitative description of singuiarities in the experimental dependences at f > 0.6.Nomograms for determining the superconducting volume fraction in high-T, superconductors were constructed.
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