Title :
Phase transformation and magnetic properties of nanocrystalline Fe 73.5Cu1Nb3Si22.5-xBx (x=6,9) alloys
Author :
Vázquez, M. ; Marin, p. ; Leccabue, F. ; Watts, B.E. ; Deriu, A. ; Negri, D. ; Bocelli, G.
Author_Institution :
Inst. de Ciencia de Mater., CSIC, Madrid, Spain
fDate :
11/1/1993 12:00:00 AM
Abstract :
The coercivity and phase transformations of Fe73.5Cu 1Nb3Si22.5-xBx nanocrystalline alloys as a function of temperature (540 and 620°C), annealing times (up to 240 min), and composition (x=6 and 9) are investigated by means of magnetic measurements, Mossbauer spectroscopy, and X-ray diffractometry. Nanocrystalline microstructure after annealing at 540°C gives rise to a softening of the material, while, after annealing at 620°C for short times, a magnetic hardening is observed before a significant increase in size of the α-Fe(Si) grains and the detection of a secondary Fe2B phase. The initial stages of Fe2B precipitation seem to be responsible for this magnetic hardening
Keywords :
Mossbauer effect; X-ray diffraction examination of materials; annealing; boron alloys; coercive force; copper alloys; crystallisation; ferromagnetic properties of substances; grain growth; iron alloys; magnetic properties of amorphous substances; melt spinning; metallic glasses; nanostructured materials; niobium alloys; precipitation; silicon alloys; 0 to 240 min; 540 to 620 C; Fe2B precipitation; Fe73.5Cu1Nb3Si22.5-xB x; Mossbauer spectroscopy; X-ray diffractometry; annealing temperature; annealing times; coercivity; composition dependence; magnetic hardening; magnetic properties; nanocrystalline; phase transformations; secondary crystallisation; softening; Annealing; Coercive force; Copper alloys; Iron alloys; Magnetic materials; Magnetic properties; Magnetic variables measurement; Niobium alloys; Silicon alloys; Temperature;
Journal_Title :
Magnetics, IEEE Transactions on
