Alodine 5200 vs. Alodine 1200 Conversion Coating for Aluminum

A. You'd be best off contacting the maker of the Alodine line of products. I do believe it's Henkel Surface Technologies.

I'm assuming you're looking for a QPL certified product that would fit your needs?

A. Alodine 1200 is a chromate conversion coating, while Alodine 5200 is a non-chrome titanium based conversion coating. The non-chrome treatments are designed to replace chromate conversion coatings in applications where they can't be used for environmental/safety reasons. Non-chrome coatings tend to be more expensive than chromates and they typically require tighter process control to ensure consistent performance.

A. Alodine 5200 is a substitute pretreatment for aluminum substrates. It does not contain hexavalent chromium, which has become an issue as of late. It has just recently been endorsed by TACOM as a substitute for chromate conversion coatings. It is not yet commonly used and does not totally duplicate the results of typical conversion coatings such as Alodine 1200. I agree with other correspondent that the best route for answers is to contact the supplier Rep. The supplier is Henkel Technologies.

A. The main difference between Alodine 5200 and Alodine 1200 is that Alodine 1200 contains hexavalent chromium. the 1200 makes the aluminum turn a goldish color and the 5200 does not. I work in a paint shop that deals with both chemicals to treat parts for painting. The parts we build are for the striker tanks for the army.

Hexavalent chromium might sound familiar to you because there is a movie based on its effects, its called Erin Brockovich [affil link to Amazonaffil links]. So for all you military guys this movie is all true. Even after the part is treated with 1200 and after it is dry it is very dangerous to be handling unpainted treated parts without rubber gloves ⇦this on eBay or Amazon [affil links] and other protective gear. Alodine 1200 when in contact with skin seeks calcium and goes right for the bones. It might not affect you right away but you might have problems down the road sometime.

---

Hi Jean-Paul. I believe it's good that we are rapidly moving away from coatings that leave hexavalent chromium on the parts -- as you say, it's carcinogenic. And I also believe that workers should wear gloves to reduce exposure.

But every consumer has chromated components all around their house, and has for decades. All those iridescent yellowish parts on hinges, door hardware, lamp sockets, lightbulbs, tools, etc., that look sort of brass colored but aren't brass are the hexavalent chrome coatings you are speaking of; and a smaller concentration is on many parts that are more silvery colored like electrical boxes, pipe, conduit, most nuts and bolt, etc.

So I think the phrase "very dangerous" is a little bit exaggerated, although again I agree that gloves should be worn on the job. "Goes right for the bones" applies to hydrofluoric acid, not chromate. While there might be a low concentration of fluoride in the process solution itself, I think it is greatly exaggerated to worry that your bones will be attacked if you touch chromated parts.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

A. Hi Shahid. Mil-C-5541 -- actually MIL-DTL-5541 [on DLA] these days -- is a military standard for conversion coating. Associated with it is a Qualified Products Database, QPL-81706, which lists the products which can be applied for the creation of the coating. Henkel has a number of Alodine products listed there, but I don't think 5200 is on the list. You can either check the QPL or check with Henkel. Good luck.

Regards,