Effect of thermal treatments on the high-frequency magnetic permeability of glass-covered Co83.2Mn17.6Si5.9B3.3 wires

Samples of glass-covered Co83.2Mn17.6Si5.9B3.3 wires have been used as inner conductors of a section of coaxial line, whose reflection parameter has been measured by means of a network analyser. From high-frequency magneto-impedance data it is possible to extract information about the magnetic permeability of the sample, as a function of frequency or of an externally applied static longitudinal magnetic field. Curves of relative circular magnetic permeabilities are reported for as-prepared, conventionally annealed and Joule-heated samples. Features of the permeability curves displaying a ferromagnetic-resonance-like behaviour are shown and discussed.