XPS Studies of Oxide Growth and Segregation in Aluminium-Silicon Alloys

✍ Scribed by Werrett, C. R.; Pyke, D. R.; Bhattacharya, A. K.

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 285 KB
• Volume: 25
• Category: Article
• ISSN: 0142-2421
• DOI: 10.1002/(sici)1096-9918(199709)25:10<809::aid-sia304>3.0.co;2-m

✦ Synopsis

The oxidation of three aluminium-silicon alloys has been studied as a function of temperature. At temperatures below 473 K a thin passivating oxide Ðlm is formed. At higher temperatures the segregation of the trace element magnesium to the surface is observed where it dominates the subsequent oxidation behaviour. In the absence of oxygen, magnesium segregation does not occur. From these results it is concluded that at temperatures in excess of 473 K magnesium segregation controls oxide growth and also that the degree of segregation is temperature dependent. Segregation e †ects are also observed for sodium, which appears to be concentration limited, and silicon, which is conÐned to the alumina-rich regions close to the metal surface where the silicon is also oxidized. 1997 ( by John Wiley & Sons, Ltd.