Investigation of the Nanocrystallization Process and the Magnetic Properties of Finemet-Like Fe_(73.5)Si_(17.5)B_5Nb_3Cu_1 Ribbons

摘要

The crystallization evolution and the soft magnetic properties of a a Finemet-like nanocomposite ribbon, Fe_(,SCN17B5.135 have beieunb in37ve)stiga(ted by using diferential scaning calorimetry (DSC) and thermomagnetic measurements. The results show that DSC curve exhibits two clearly exothermal peaks, one at 535℃ and the other at 670℃, which are related to crystallization of the α-Fe(Si) and the boride phases, respectively. The crystallization activation energy is evaluated by using two models, the Kissinger model and the Johnson-Mehl-Avrami (JMA) model, which are consistent with each other. Ultrasoft magnetic properties are obtained after proper annealing due to the formation of an appropriate volume fraction of nanostructured α-Fe(Si) embedded in a residual amorphous matrix to compensate the total magnetostriction. The influence of the annealing process on the soft magnetic properties of the studied sample was investigated and is discussed.