Rev.Adv.Mater.Sci. (RAMS)
No 5, Vol. 18, 2008, pages 469-475

CRYSTALLIZATION BEHAVIOR OF AMORPHOUS ALLOYS IN THE Al-Ce-Ni SYSTEM

C. Triveño Rios, S. Suriñach, M. D. Baró, C. Bolfarini , W.J. Botta and
C.S. Kiminami

Abstract

This work involved an investigation of the crystallization process of Al90Ce5Ni5 amorphous alloy. Rapidly quenched amorphous ribbon was produced by melt-spinning and the structural transformations occurring during heating were studied using a combination of X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Crystallization took place through a multi-stage process. The first stage of transformation corresponded to the crystallization of the fcc-Al phase, while the second and third exothermic transformations involved the crystallization of Al3Ni, Al11Ce3, Al3Ce, AlCeNi and unidentified phases. The transformation curves recorded under isothermal treatments at 150 úC and 305 úC indicated that crystallization occurred through nucleation and growth, with diffusion-controlled growth occurring in the first crystallization stage and interface-controlled growth in the third. The Avrami exponents suggested only crystallization of fcc-Al phase, and simultaneous crystallization of intermetallic compounds and unidentified phases with two- and three-dimensional crystallization.

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