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Corrosion prevention

 

Can a manufacturer or anyone in authority confirm whether Alodine 1200S when left dried on aluminum surfaces cause corrosion? Would appreciate a qualified answer.

Thank you.

Lee Yee Kong
- Singapore

I can not claim this as a qualified answer but from experience. I had some pieces 'Alodined' then blow dried. However, it turned out that there was still solution trapped in the holes. They leaked overnight, and the next day we discovered the area around the holes were either discolored or slightly corroded. Remember that the Alodine solution itself is acidic ,therefore, is corrosive to the metal.

Dado Macapagal
- Toronto, Ontario

Thanks Dado, Experiences are as good as anything. This means to say that Alodine should never be allowed to flow into crevices where rinsing is difficult. As would be in assembled joints like those in aircraft structures. I wonder if there are anyone else with similar experiences.

Lee Yee Kong
- Singapore

I'd like to add that it also depends on the amount of Alodine solution that will be left dried on the surface. If it is only brushed or wiped to impart a thin coating, then this will not be detrimental on the parts. In fact this is the way we do it for touch ups.

Dado Macapagal
- Toronto, Ontario