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Problems with chromium bath

June 16, 2008

Hello, I'm Carolina Alvarado I'm a student of Chemical Engineering, actually I'm working in my Thesis topic and it's about electroplating on ABS, in my country Colombia this process may be is a little backward respect the world industry, but I hope that change. In the plant where I work we have a problem with Chromium bath, because we want give more time in the bath but is impossible, because the pieces tend to burn, actually the bath conditions are:
Chromic acid: 250 g/l
sulphate: 3 g/l
Temperature: 35-45 °C
Time: 1 min
Current density:5-30 Amp/dm2 (depend de cathode surface)
could you help us please we don't know what is the problem...

Carolina Alvarado
student - Bogotá

Pieces burn because they are being run at too high a current density, not because of the time in the tank.

James Watts
- Navarre, Florida
June 18, 2008

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We are also using chromium bath in our ABS plating process, the failure of chromium bath can be easily seen from the hull cell test.. we always use this test to see the bath condition.. and generally te amount of the H2SO4 in the bath cause problems then we add BaCO3 to our bath. Also the amper that you use is seeming too much to me..
regards ..

Eren Sakar
- Izmir, Turkey
October 19, 2008