Temperature-driven oxidation behavior on pure iron surface investigated by time-resolved EXAFS measurements
- POSTECH, Pohang (Korea, Republic of)
- K-JIST, Kwangju (Korea, Republic of). Dept. of Materials Science and Engineering
The surface-front oxidation mechanism of iron was investigated by time-resolved, glancing-angle Fe K-edge fluorescence EXAFS measurements at various oxidation temperatures of 200--700 C. The glancing angle was chosen according to the depth of the oxide layer, roughly 1,500--2,000 {angstrom}. The oxidation behavior under rapid heating (up to 600 C within 10 minutes) was compared with the slowly heated oxidation process using the Quick-EXAFS measurements. In the slowly heated process, Fe{sub 3}O{sub 4} was the dominating phase at a relatively low temperature (300--400 C) initially. However, at a relatively high temperature (above 600 C), the Fe{sub 2}O{sub 3} and FeO crystalline phases are gradually enriched as the successive oxidation process involving intrusive oxygen proceeded. Remarkably under a prolonged heat treatment above 600 C, the stable FeO phase that exists in a deep-lying interface structure and Fe{sub 2}O{sub 3} phase eventually dominates the thick front-surface structure. In a quickly heated process, however, Fe{sub 3}O{sub 4} phase is less dominating, which is contradictory to the commonly accepted oxidation models. The EXAFS results are discussed in conjunction with the x-ray diffraction features under the same heat treatment conditions.
- OSTI ID:
- 302417
- Report Number(s):
- CONF-980405-; TRN: IM9904%%205
- Resource Relation:
- Conference: Spring meeting of the Materials Research Society, San Francisco, CA (United States), 13-17 Apr 1998; Other Information: PBD: 1998; Related Information: Is Part Of Applications of synchrotron radiation techniques to materials science 4; Mini, S.M. [ed.] [Northern Illinois Univ., DeKalb, IL (United States)]|[Argonne National Lab., IL (United States)]; Stock, S.R. [ed.] [Georgia Inst. of Tech., Atlanta, GA (United States)]; Perry, D.L. [ed.] [Lawrence Berkeley National Lab., CA (United States)]; Terminello, L.J. [ed.] [Lawrence Livermore National Lab., CA (United States)]; PB: 398 p.; Materials Research Society symposium proceedings, Volume 524
- Country of Publication:
- United States
- Language:
- English
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