In:
Journal of Materials Research, Springer Science and Business Media LLC, Vol. 23, No. 2 ( 2008-02), p. 359-366
Abstract:
The isothermal oxidation behavior of Zr 2 Al 3 C 4 in the temperature range of 500 to 1000 °C for 20 h in air has been investigated. The oxidation kinetics follow a parabolic law at 600 to 800 °C and a linear law at higher temperatures. The activation energy is determined to be 167.4 and 201.2 kJ/mol at parabolic and linear stages, respectively. The oxide scales have a monolayer structure, which is a mixture of ZrO 2 and Al 2 O 3 . As indicated by x-ray diffraction and Raman spectra, the scales formed at 500 to 700 °C are amorphous, and at higher temperatures are α-Al 2 O 3 and t-ZrO 2 nanocrystallites. The nonselective oxidation of Zr 2 Al 3 C 4 can be attributed to the strong coupling between Al 3 C 2 units and ZrC blocks in its structure, and the close oxygen affinity of Zr and Al.
Type of Medium:
Online Resource
ISSN:
0884-2914
,
2044-5326
DOI:
10.1557/JMR.2008.0042
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2008
detail.hit.zdb_id:
54876-5
detail.hit.zdb_id:
2015297-8
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