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Can anodization cause brittleness?

I have a situation where a steel plug of 7mm (1/4") dia. is pressed in to an anodized sleeve. This sleeve cracks open sometimes. I want to know if anodization can contribute to brittleness. The base material is Al-Si 12% (A6061BE).

G. Muralidharan
steering systems - Chennai, TamilNadu, India
2003

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I have never heard of anodising making the aluminium brittle, but that is not to say it can't. 12%Si aluminium is not the easiest of alloys to anodise, but it does make a good bearing material. I would suspect the steel plug is slightly oversized, so check those before worrying about anodising. Also check the operating conditions and make sure there is no conflict in thermal expansions.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003