Crystallization of Fe-Based Bulk Amorphous Alloys

Abstract

Co 10 Ti 2 Y 7 B 20 alloys. The crystallization of the alloys was studied by differential scanning calorimetry (DSC). The amorphicity of the investigated alloys in the as-quenched state was testified using Mössbauer spectroscopy, X-ray diffractometry and transmission electron microscopy. Moreover, X-ray diffractometry was applied to structure investigations of partially crystallized samples. The crystallization process in the investigated alloys occurs in one or two stages. Two peaks in the DSC curves can be overlapped or well separated indicating the complex crystallization processes. From X-ray diffraction we have stated that in both types of devitrification the crystalline phase can be ascribed to the α-FeCo. In the first stage the crystalline grains seem to grow from the nuclei frozen in the samples during the rapid quenching, whereas in the second one both the growth of the existed grains and creation of new ones during annealing may occur.Keywords: bulk amorphous alloys, differential scanning calorimetry (DSC), X-ray diffractometry, transmission electron microscopy, Mössbauer spectroscopy . Amorficzność próbek w stanie po zestaleniu została zbadana przy użyciu spektroskopii Mössbauera, dyfrakcji promieni Röntgena oraz transmisyjnej mikroskopii elektronowej. Ponadto, dyfrakcję promieni X użyto do badań próbek częściowo skrystalizowanych. Na podstawie badań z wykorzystaniem DSC stwierdzono, że krystalizacja może przebiegać w jednym lub w dwóch etapach. Piki na krzywych DSC odpowiadające tym dwóm etapom mogą być położone blisko siebie lub wyraźnie rozdzielone. Pierwsze maksimum odpowiada tworzeniu się ziaren α-FeCo z zarodków powstałych podczas produkcji stopu, drugie natomiast związane jest z procesem tworzenia się ziaren fazy krystalicznej α-FeCo z zarodków powstałych podczas wygrzewania i rozrostem wcześniej powstałych ziaren.

The Influence of Heat Treatment on the Phononic Multilayer Sensor

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The Microstructural Changes due to the Heating Treatment of Magnetic Amorphous Fe81(PtRh)5Zr7Nb1Cu1B5 Alloy

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