In:
Journal of Materials Research, Springer Science and Business Media LLC, Vol. 13, No. 2 ( 1998-02), p. 504-517
Abstract:
The effect of ternary addition on the thermal stability and the sequence and the kinetics of crystallization of metallic glasses Zr 76 Fe (24− x )Ni x ( x = 0, 4, 8, 12, 16, 20, 24) have been examined. It has been found that the surface crystallization occurs in the composition range 16 〈 x 〈 20, leading to the formation of an ordered Fe-rich (Fe, Ni) 3 Zr cubic phase, followed by the transformation of the bulk to a mixture of α−Zr and Zr 2 Ni. Crystallization of alloys containing 12 to 20% Fe occurs at lower temperatures by primary crystallization of Zr 3 (Fe, Ni), followed by decomposition of the remaining amorphous matrix by eutectic crystallization giving rise to α−Zr + Zr 2 Ni. At higher temperatures these alloys transform polymorphically to Zr 3 (Fe, Ni) in which Ni partially substitutes Fe in the Zr 3 Fe lattice. Copious nucleation of Zr 3 (Fe, Ni) phase in these alloys, leading to the formation of a nanophase structure, has been observed. This is consistent with the prediction of increasing nucleation rate for Fe-rich compositions. The crystal nucleation and growth kinetics have been examined for primary, eutectic, and polymorphic crystallization processes. The observed nucleation and growth behaviors have been rationalized by considering the role of the quenched in nuclei and the activation energies of nucleation and growth.
Type of Medium:
Online Resource
ISSN:
0884-2914
,
2044-5326
DOI:
10.1557/JMR.1998.0065
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
1998
detail.hit.zdb_id:
54876-5
detail.hit.zdb_id:
2015297-8
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