Metal finishing Q&As since 1989

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Best coating for aluminum hotplate?

2006

Hi,
Can anyone advise as to the best pre-treatment if any of a cast aluminum hotplate that will reach a temperature of 400 deg C. Material is LM6. It will be used in laboratories where chemicals will come into contact with the surface.

Thanks

Andy Mellor

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There is no perfect solution.
Anodize by itself is vulnerable to caustic material.
Hard anodize with a coat of teflon (many kinds, so be careful) would probably do well.
Electroless nickel should stand up to most chemicals, but will turn many colors with the heat and a number of things will leave stains.
A true ceramic, probably plasma sprayed and honed might be worth trying.
Fired porcelain is also an option.

James Watts
Navarre, Florida
2006

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Andy,
I think 400 °C is not an advisable temperature for aluminum. It is so close to its softening temperature. Complete melting comes at around 650 °C. Maybe you should consider another base metal for safety reasons.

Guillermo Marrufo

2006

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Teflon will not work well at this temp.
The best solution is enamel, it will resist most of chemicals products at this temperature.

Jordi Pujol

2006