Title :
Mossbauer spectroscopy in nanocrystalline materials
Author :
Pulido, E. ; Navarro, I. ; Hernando, A.
Author_Institution :
Inst. de Magnetismo Aplicado, Univ. Complutense de Madrid, Spain
fDate :
9/1/1992 12:00:00 AM
Abstract :
Amorphous-to-crystalline transformation after isochronal annealing of as-quenched ribbons with the composition of Fe73.5Si13.5B9CuNb3 has been investigated by Mossbauer spectroscopy. X-ray diffraction, differential scanning calorimetry, and transmission electron microscopy studies were performed to complement the Mossbauer results. The crystallization was found to consist of at least two steps. In the first step, precipitation of Fe-Si alloy (18-20% Si) with DO3 structure takes place, coexisting with an amorphous phase. In the second step the amorphous phase crystallizes, and Fe2B is found. The final crystalline products are Fe-Si, Fe-B, and a small amount of nonferromagnetic phase. This nonferromagnetic phase is suggested to be the cause of the magnetic hardening
Keywords :
Mossbauer effect; boron alloys; copper alloys; crystallisation; ferromagnetic properties of substances; iron alloys; magnetic properties of amorphous substances; magnetisation; metallic glasses; nanostructured materials; niobium alloys; silicon alloys; DO3 structure; Fe73.5Si13.5B9CuNb3; Mossbauer spectroscopy; X-ray diffraction; amorphous-crystalline transformation; as-quenched ribbons; crystallisation; differential scanning calorimetry; isochronal annealing; magnetic hardening; nanocrystalline materials; nonferromagnetic phase; precipitation; transmission electron microscopy studies; Amorphous materials; Annealing; Calorimetry; Crystallization; Iron; Nanostructured materials; Scanning electron microscopy; Spectroscopy; Transmission electron microscopy; X-ray diffraction;
Journal_Title :
Magnetics, IEEE Transactions on
