Study of magnetic after-effects of complex permeability in amorphous CoFeCrSiB alloys

In our work we have investigated magnetic after-effect (MAE) of complex permeability (μ = μ1 − jμ2) in nearly non-magne-tostrictive ferromagnetic alloys CoFeCrSiB. MAE is represented by a relative change of both real (r1) and imaginary (r2) parts of the complex reluctivity Δ/( = 1/(#x003BC; − 1)) which may be expressed as follows: Δr1(t)/r1 = r1(t) − r1(t1)/r1(t1), Δr2(t)/r2 = r2(t) − r2(t1)/r2(t1) Time t1 was 0.9 s for each measurement. Temperature dependences of both real (μ1) and imaginary (μ1) parts of complex permeability were measured in the temperature interval from − 175 to 100 °C. Computer analysis was made to evaluate the spectra of activation energies connected with MAEs. It was found that the MAE spectrum with a maximum at about 100 °C corresponds to the spectrum of activation energies with the most probable value 1.1 eV and τ0 = 5.10−15 s.