F.A. Khan

Thermoelectric Power of Some (Fe1—xMnx)75P15C10 Amorphous Alloys

The thermoelectric power S of (Fe 1-x Mn x ) 75 P 15 C 10 ferromagnetic metallic amorphous alloys with x = 0, 0.05, 0.20, 0.30 has been measured in the temperature range 30 K < T < 350 K. For all compounds, the sign of S is negative, suggesting that the transport properties are dominated by electrons. A humplike structure at low temperatures which is superimposed to a linear rise and seemingly correlated to magnetic order suggests in particular magnon drag added on diffusion thermopower as the main contributions to S(T).

Devitrification of Co‐Based Amorphous Alloys, Enhanced Initial Permeability and Giant Magneto‐Impedance

Devitrification of Co‐based amorphous alloys, enhanced initial permeability and giant magneto‐impedance have been studied for the samples of composition, Co68Fe4Ni1Si15B12, Co67Fe4Ni2Si15B12 and Co67Fe4Mo2Si15B12. Ultra‐soft magnetic properties has been observed by appropriate annealing manifested by high initial permeability of the order of 104 and low relative loss factor of 10−6. Giant magneto‐impedance ratio (GMIR) has been obtained for these compositions measured with a current driving frequency of 4.5 MHz. Field dependence of GMIR response varies for different composition and annealing condition.