Salts Build-up Around The Top of The Cathodes
The aluminum cathode bars in our Type II anodizing tank have become completely encrusted with white “salts” at the solution/air interface.
Q. The aluminum cathode bars in our Type II anodizing tank have become completely encrusted with white “salts” at the solution/air interface. I would normally think that this was a build-up of aluminum sulfate, but I thought this only happened when the concentration of dissolved aluminum in the bath was higher than normal. The aluminum in this bath is less than 2 g/L. What do you think is going on? J.M.
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