Permeabilities of metallic glasses at high magnetization rates

Domain models for dynamic magnetization of metallic glasses are discussed together with their predictions for the behavior of pulse permeability and maximum permeability. The effect of voltage excitation waveshape on losses is calculated for both bar-domain magnetization and saturation-wave magnetization. Metallic glasses of both iron and cobalt-based compositions with induced anisotropy energies between 50 and 90 J/m³ have been measured at times-to-saturation between 60 ns and 100 μs. Measurements are also given of saturated permeabilities to 10 kA/m. The ratio of losses at constant dB/ dt excitations to those occurring with 1-cosine excitation is calculated for different models of domain behavior