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Process worker would like some info on the Scientific Definition for Chromic Anodising?

I am a process operator at a leading Aerospace company. I work on a Chromic Anodising line and would like to know the science / chemical reactions behind this chemical process to understand my work better.

Daniel Malcolm Jones

2006

It is using electricity, DC, anodically, forming oxygen at the surface of the clean aluminum forming aluminum oxide. Because of the temperature, it is a thin and not terribly hard covering and will contain some chrome in the pores. Sealing in a hot chromate tank collapses the top of the pore sealing a trace of moisture in. Chromic is used mainly in aircraft where you can not get to it and there is a fear of trace leakage of sulfuric acid if normal anodizing were used.

James Watts
Navarre, Florida
2006

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2006

Daniel
I wish more questions were seeking to understand instead of just asking for instant answers.
The best way of getting involved (in UK) is to contact the Institute of Metal Finishing. The rules do not allow me to include contact details but they are not difficult to find.
They run distance learning courses for all levels of plating technicians.
Iach id da

Geoff Smith
Hampshire, England