Where the
world gathers for metal finishing
Q&As since 1989


-----

Problems in Experiment on Chemical Conversion Coating of Aluminium

I am a 4th year metallurgy student and I will perform an experiment to demonstrate chromate conversion coating of aluminium. But I have problems in the chemicals, such that; From the books,documents I read in the library and from the documents I downloaded from the internet mention about chemicals generally (Na chromate, K-dichromate, etc) or some trade named chemicals, which contain stabilizers or sth catalytic I assume, as a ready mix. So here my problem arises. Will it be easy if I use the chemicals in defined proportions in my experiment or do I really have to purchase trade name chemical(s).

P.S. I don't have academic support from my professor, as I am fully responsible from all features and problems of the project. Thanx for all the future support.

Murat Dil
Middle East Technical University - Ankara, TURKEY
2001

Hi, Murat.

People who do conversion coating for a living, and who have acquired years of experience, almost universally use proprietary chemicals instead of trying to formulate their own. So, if you are trying to demonstrate good conversion coating, you should certainly get proprietary chemicals as well. It depends on whether you are trying to demonstrate the process or determine the effects of the various chemicals in the mix.

If I were you, I think I'd try to find a shop that does conversion coating of aluminum, and try to get some hands-on help.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2001

If I were you I would follow his advice. Some Chemicals are not worth the trouble.

Ronald Higgins
- Sumter, South Carolina
2005