Crystallization kinetics of melt-spun Mischmetal-FeB-(Ti, Co and Al) permanent magnets

Abstract

The crystallization kinetics of melt‐spun Mischmetal (MM)‐FeB–(Ti, Co and Al) permanent magnets has been investigated by differential scanning calorimetry (DSC), X‐ray diffractometry, electron microscopy. The activation energies obtained in this study were E = 241.12 kJ/mol, 97.00 kJ/mol, 182.93 kJ/mol, 194.00 kJ/mol for MM‐FeB, MM‐FeB–Ti, MM‐FeB–Co–Al, MM‐FeB–Al ribbons, respectively. The exothermic curve MM‐FeB, MM‐FeB–Co–Al, MM‐FeB–Al ribbon, related to crystallization reaction is flatter and wider than that shown in a MM‐FeB–Ti alloy suggesting much lower kinetics of crystallization. The crystallization rate increased by partial substitution of Ti for Fe on Mischmetal‐FeB permanent magnets. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)