| Autor: |
Czyrska-Filemonowicz, Aleksandra, Szot, Krzysztof, Wasilkowska, Anna, Tyagi, Akilash Kumar, Quadakkers, Willem J. |
| Zdroj: |
Journal of Electron Microscopy; January 1999, Vol. 48 Issue: 6 p725-725, 1p |
| Abstrakt: |
The growth phenomena of protective scales formed on mechanically alloyed oxide dispersion strengthened alloys were studied using quantitative structural analyses (atomic force microscopy as well as transmission and scanning electron microscopy) in combination with secondary ion and secondary neutral mass spectrometry. The main emphasis was placed on the early stages of the oxidation process when the oxide film is just a few nanometres thick. The scale morphology, composition and growth during short-time exposure (up to 180 mm) of the ferritic oxide dispersion strengthened alloy INCOLOY MA956 at 800 and 1000�C in air were found to be dependent on oxidation conditions (time and temperature) as well as the substrate crystallographic orientation. The growth mechanism of the alumina scales in the early stages of oxidation seemed to be dominated by outward cation diffusion, contrary to the later stages (1000�C/180 mm) when an inward grain boundary oxygen diffusion becomes dominant. Oxide grain boundary density and consequently oxide growth by grain boundary diffusion appeared to depend on the crystallographic orientation of the alloy. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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