Temperature dependent crystallization of amorphous Y67Fe33 studied by kinetic small angle neutron scattering
نویسندگان
چکیده
Temperature-resolved small angle neutron scattering has been used to study the nucleation, growth kinetics and crystallite morphology in the Y-Fe system. Crystallization from amorphous Y67Fe33 to the YFe2 Laves phase via a novel ‘YFe’ intermediate phase has been followed to completion as a function of temperature from 180oC to 500oC. The SANS results agree well with published kinetic neutron diffraction data. Below 390oC, diffraction data suggest that SANS arises solely from the contrast between crystalline Y and the Fe-rich amorphous matrix. Between 390oC and 410oC all temperature variables are seen to form a sharp peak. This suggests that critical scattering occurs at Tc≈400oC. This critical scattering implies full crystallization of Y67Fe33 occurs over a very narrow (~20oC) temperature range.
منابع مشابه
Synthesis and characterization of a novel Y–Fe phase via kinetic neutron diffraction
Kinetic in situ neutron diffraction has been used to study the crystallization of amorphous Y67Fe33. The results show that partial crystallization first occurs close to 300 ◦C where the Y phase is formed. The entire sample crystallizes at 390 ◦C and new Bragg peaks appear, signifying the formation of a novel Y–Fe phase. This new phase coexists with Y to 450 ◦C when the Bragg peaks associated wi...
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