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Boehmite from boiling in water compared to commercial anodization

We are a small manufacturer of machines. We typically clear or black anodize our machine components, this is done on a lot charge basis by our vendor. On occasion we need to anodize or finish a single part. Could we simply boil the part for 20 hours in RO water and achieve pretty much the same effect.

Gary Hillman
support specialists - Montville, New Jersey
2006

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First of three simultaneous responses --

We are a small manufacturer of machines. We typically clear or black anodize our machine components, this is done on a lot charge basis by our vendor. On occasion we need to anodize or finish a single part. Could we simply boil the part for 20 hours in RO water and achieve pretty much the same effect.
Gary Hillman

Hi Gary!
I can't help but chuckle as this is how most of our customers think.
Anodizing is a bit more complicated and RO water has little to do with it other than rinsing. Anodizing involves acids and a good amount of electrical current put simply.
To answer your question, no Gary you cant.

Bill Grayson
metal finishing - San Jose, California, USA
2006

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Second of three simultaneous responses --

That depends highly on what you mean by "pretty much the same effect". It would not be as thick nor as abrasion resistant, but the resulting coating would be very corrosion resistant and non-conductive (I think).

I don't know the exact characteristics of such a coating, but according to the Fifth Edition of "The Surface Treatment and Finishing of Aluminum and its Alloys" (page 475, volume 1) it will be "thin but highly protective" and is evidently not used more often due to the relative cost of boiling something for 20 hours.

Jim Gorsich
Compton, California, USA
2006

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Third of three simultaneous responses --

No

Khair Shishani
aircraft maintenance - Al Ain, UAE
2006