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

Abstract

In our work we have investigated magnetic after-effect (MAE) of complex permeability (μ = μ 1 − jμ 2) in nearly non-magne-tostrictive ferromagnetic alloys CoFeCrSiB. MAE is represented by a relative change of both real ( r 1) and imaginary ( r 2) parts of the complex reluctivity Δ/( = 1/(#x003BC; − 1)) which may be expressed as follows: Δr 1(t)/r 1 = r 1(t) − r 1(t 1)/r 1(t 1), Δr 2(t)/r 2 = r 2(t) − r 2(t 1)/r 2(t 1) Time t 1 was 0.9 s for each measurement. Temperature dependences of both real (μ 1) and imaginary (μ 1) 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 τ 0 = 5.10 −15 s.