Abstract
AC-initial susceptibility (χac) studies on a wound cores of as-spun amorphous and rapid-thermal-annealed nanocomposite Fe88Nd6B6 alloy ribbons were performed at room temperature to 700°C. A quantitative method of estimating the amount of residual amorphous phase in heated ribbons was derived from the χac peak intensity of the amorphous phase. The fall width at half maximum of χac peak corresponding to Curie temperature of Nd2Fe14B phase was found to quantitatively related to the extent of exchange coupling between the two phases due to its linear increase with increasing nano-grain-size, while the remanence ratio decrease. Tc of the Nd2Fe14B nano-phase was found to decrease with increasing grain size.
