Published online by Cambridge University Press: 26 February 2011
FeCo-based nanostructured powders were prepared by mechanical alloying and subsequently heat treated in an attempt to reduce their coercivity, HC. Although the powders had grain sizes smaller than the magnetic exchange length, a low HC, as expected from Herzer's model, did not occur. The results of magnetic measurements on dilute and concentrated samples of the powder, as well as measurements of the temperature dependence of the magnetic properties from 10-300 K, indicate that the degree of magnetic interaction between the individual powder particles determines the relatively high HC of 10-20Oe at room temperature.