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Alodine 1200S vs. 1201; Alodine vs. Alochrom

TUTORIAL:
(to provide context, hopefully helping readers more quickly understand the Q&A's)

Alodine is a Henkel trade name mostly used for their line of chromate conversion coating chemistry for aluminum.
The most common spec for this process is MIL-DTL-5541 [on DLA].
It is sometimes called 'chem film', especially in the USA.
Iridite is an Enthone/Macdermid trade name for their chemistry for this process.

Q. Customer called out Alodine 1201 ⇦this on eBay or Amazon [affil links] as a replacement for Alodine 1200S. What is the difference between these products?

Best Regards, Menno Velthuijs.

Menno Velthuijs
- Nieuw Vennep, Holland, Europe
1999

A. Alodine 1201 ⇦this on eBay or Amazon [affil links] is a ready-to-use chromate conversion chemical; that is, for its original purpose there are no make-up or control parameters to be concerned about. In terms of U.S. military specifications, which many aircraft companies use as a guide, it is qualified under the Qualified Products List MIL-DTL-81706 [on DLA] as a brush-on only. It was created primarily for touch-up and repair of scratched surfaces which had been previously anodized or chromated. If not tied into a specification such as the above, it can be diluted 1 part: 2 parts water to make an immersion bath for chromating new parts. As a bath it can be controlled like Alodine 1200S.

Alodine 1200S is a powder, chromate conversion chemical which must be dissolved in water to make a bath, which is then used to chromate aluminum. Under the QPL it is qualified for immersion, spray, or brush-on coatings. In terms of processing aircraft parts, AL 1200S has been the benchmark of the industry for over 40 years. Alodine 1201 ⇦this on eBay or Amazon [affil links] is similar to a 20 gram per liter solution of Alodine 1200S. The AL 1200S can be used anywhere AL 1201 is used, but for large amounts of touch-up work or if handling of a liquid is preferred, AL 1201 is more convenient.

We are not aware of immersion baths of Alodine 1201 being used on a long-term basis, and if the reason for using it is strictly to handle liquids, we have another liquid product on the above QPL, Alodine 1600, which was designed for long- term use in immersion or spray baths.

Phil Johnson
- Madison Heights, Michigan

Multiple threads merged: please forgive chronology errors :-)

Q. My question is about Alodine 1200S and Alodine 1201 ⇦this on eBay or Amazon [affil links] . Is Alodine 1200S considered an oxidizer? And is Alodine 1201 a corrosive? or vise-versa. A fellow co-worker had asked me this. I would like to know myself whether this is correct.

Thanks,

Al Rueda
American Eagle Airlines - DFW Airport, Texas, U.S.A.
2002

A. Alodine is a brand name (Henkel), not a generic type of process. Contact the chemical manufacturer with these specific questions.

Tim Neveau
Rochester Hills, Michigan

Q. Is Alodine 1200s the same as Alochrome 1200. I believe that the European trade name is Alochrome but the 2 products are one of the same thing. Am I right in thinking this?

Lee Franckeiss
- England
2002

A. Yes you are perfectly correct.

Ciaron Murphy
- Great Britain

A. The following statement is taken from a document produced jointly by Trimite (our supplier for Alocrom 1200) and Henkel Technologies UK.

"Alodine 1200 is chemically identical to Alocrom 1200"

Richard Mosley
metalsmiths - UK

Q. I am UK based and have an enquiry from an American customer for a part with an Alodine 1000 (clear) finish, my metal finisher has offered Alochrome 1000 as an alternative and I need to know if this is a suitable alternative, The part is going in a vacuum environment and must not out-gas or give off any vapours which might affect the process.
Thanks Graham.

Graham Coleman-Hill
product designer - Shebbear, Devon, UK

A. Hi, Graham. I appreciate Mr. Mosley taking the time to quote the Henkel documents, but manufacturers can reformulate trade name products at any time, so I'd inquire of Henkel directly at the time of use. Good luck.

Regards,