Oxidation of a ternary Cu-Ni-Fe alloy under low oxygen pressures at 800-900 degrees C

Citation
Ys. Li et al., Oxidation of a ternary Cu-Ni-Fe alloy under low oxygen pressures at 800-900 degrees C, J ALLOY COM, 317, 2001, pp. 578-582
Citations number
16
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
JOURNAL OF ALLOYS AND COMPOUNDS
ISSN journal
0925-8388 → ACNP
Volume
317
Year of publication
2001
Pages
578 - 582
Database
ISI
SICI code
0925-8388(20010412)317:<578:OOATCA>2.0.ZU;2-6
Abstract
Tile oxidation of a Cu-based ternary alloy containing 30 at% Ni and 25 at% Fe has been studied at 800-900 degreesC under low oxygen pressures. The all oy contains a mixture of a phase a: rich in Cu and Ni with little Fe with a phase beta rich in Fe and Ni with little Cu. The scaling kinetics show rat her large deviations from the parabolic law and are milch slower than those of purr Fe and of a binary Cu-25Fe alloy oxidized under the same condition s. The growth of an external layer of iron oxide is coupled to the formatio n of oxide particles dispersed uniformly within the alloy. The internal oxi dation of Fe produces a transformation of the beta phase into the Cu-Ni sol id solution which becomes the matrix of the internal oxidation zone. The U phase disappears also beneath the internal oxidation front to some depth, p roducing a single-phase cu layer, The spatial distribution of the oxide par ticles in the alloy is rather uniform and does not correspond to that of th e two-phases in the original material, which have a largely different iron content, This is the result of a transformation of the beta phase into the alpha phase and of the lateral diffusion of the various components through the alpha layer before the arrival of the internal oxidation front. (C) 200 1 Elsevier Science B.V. All rights, reserved.