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  for Metal Finishing since 1989
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Coating for protecting aluminum from water with chlorine?

2005

Hello all, I have a dilemma:
I have been designing a heat exchanger that obviously has to be made out of a material with a resonable thermal conductivity. Therefore, aluminum seems to be a good choice, however, this heat exchanger will be put directly in contact with water from a household plumbing system. I wonder whether this water has a chlorine concentration that would attack this heat exchanger. If so, please, could you tell me what kind of coating or treatment should I use in this aluminum heat exchanger to prevent corrosion without degradating heat transfer?
Thank you,

ANDERSON BORTOLETTO
appliances - Joinville, SC, Brazil

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You will have to treat the water or change the heat exchanger material to copper or something else. Aluminum is very active (sensitive to attack) therefore, no coating is safe enough to protect it. Any pore, crack or discontinuity in the cioating will result in a concentrated attack and greater damage.

Guillermo Marrufo
Monterrey, NL, Mexico
2005

In such case, you may use titanium heat exchanger for the said application.

R. Annakumar
- Chennai, Tamilnadu and India
2005