Curie temperature measurement of metastable alloys using high heating rate

The Curie temperatures (Tc) of amorphous CoxFe85 − xB15, amorphous and partially crystallized FINEMET metastable alloys were investigated by high heating rate a.c. magnetic measurements. For the Co alloys, the aim was to increase the crystallization temperature above the Curie temperature, using the highest possible heating rate. The highest heating rate achieved was 113 K s−1 (6780 K min −1). This was enough only for CoxFe85 − xB15 alloys with low x-values to avoid crystallization below the Curie temperature. At higher x-values, the crystallization was found to be very near to Tc. Extrapolations of the Curie temperature could be made better than has previously been the case in the literature.