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Need Source of Iridite

I am looking for a source of Iridite - a chemical used for finishing aluminum. A Canadian source is preferred, but any source would be appreciated.

Thanks,

Roelof Datema
Nortel
1996

Ed. note: Sorry, this RFQ is old & outdated, so contact info is no longer available. However, if you feel that something technical should be said in reply, please post it; no public commercial suggestions please ( huh? why?)

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This material used to be available through Witco Allied Kelite. However, Witco sold the metal finishing portion of their business to, and you might contact, MacDermid to inquire if they still carry that product. Also, there are many other companies that manufacture similar conversion coating products (refer to QPL-81706 [on DLA]).

Blair Smith
aerospace - Windsor Locks, Connecticut
1996

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Hi, I would like to know the difference between Iriditing & Anodizing (i.e when should one be used over the other, conductivity, material composition … ) Any data sheets or information will be greatly appreciated.

Thank You

Leo Minervini
- Saddle Brook, New Jersey
2000

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2000

Hello, Leo. Iridite is a proprietary brand name for process chemistry for MIL-C-5541 chromate conversion coating. Anodizing offers greater corrosion resistance than chromate conversion coating, but costs more because it is an electrolytic process, and a time consuming one, rather than a simple and quick immersion process.

Chromate conversion coated surfaces are fairly conductive, whereas anodized surfaces are insulators. Chromate conversion coating is clear or gold-ish, anodized finishes can be dyed many different colors. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

I am looking for the thermal-optical properties of aluminum coated by Iridite, including literature references

Hans Peter Schmidt
aerospace center - Koeln, Germany
2000

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Iridite is a brand name for MIL-C-5541 chromate conversion coating chemistry. Chromate conversion coating preserves the conductivity of aluminum, whereas anodizing builds an electrically non-conductive aluminum oxide film. Chromate conversion coatings may or may not be subsequently painted. Anodized finishes can be painted, but rarely are. Anodizing offers greater corrosion resistance.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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I need a source for a Yellow Iridite touch up-Pen to touch up scratches in yellow Iridited aluminum.

Jon H [last name deleted for privacy by Editor]
- Lynchburg, Virginia
2000
2002

Ed. note: Sorry, this RFQ is old & outdated, so contact info is no longer available. However, if you feel that something technical should be said in reply, please post it; no public commercial suggestions please ( huh? why?)

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I would like to know the difference between Iridite 14 and Alodine 1200. I know that these processes refer to the same MIL-C-5541 but it's not clear if they are equivalent or exactly the same thing.

Romani Romano
- Milano, Italy
2002

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Hello, Romani. Iridite is a Macdermid trade name for MIL-C-5541 chromate conversion coating products and Alodine is a Henkel trade name for the same type of coatings.

Coke and Pepsi are both cola soft drinks but they are not exactly the same thing. Plus there is Diet Coke, Original Coke, New Coke, etc. It's the same thing with chromate conversion coatings: there are clear and yellow coatings, cyanide-free and cyanide-bearing chemistries, trivalent and hexavalent, dry-in place and rinseable coatings, etc. Plus there is one more distinguishing factor: some of them are accepted as qualified products for MIL-C-5541 per QPL-81706 [on DLA] and some are not. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

How are the conductive properties of clear Iridite?

Don Wood
engineer - Brockton, Massachusetts, USA
April 22, 2010

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April 22, 2010

Hi, Don. The coating is probably not actually conductive, but the clear chromates are exceptionally thin so as to not interfere with the conductivity of the aluminum. Iridite is a Macdermid trade name for a host of chromate conversion coatings, so the exacting fine detail would probably vary from one to another just as General Motors various Chevrolets have different properties. But the general answer is that Mil-DTL-5541 specifies the requirements for these chromate conversion processes.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey