We use acid zinc as our main production. We have a problem in black chromating process, on the surface of the part we found several white spots. Why ?
Kasmin Gurning - Cikarang, Jakarta, Indonesia 2001
Kasmin first are you using a proprietary silver nitrate black chromate? Second, following rinsing after plating what are you using for a neutralization step, dilute acid? Are you rinsing in a tank following the black that is clean? Is this an automatic machine or hand line?
Bill Hemp tech svc. w/ chemical supplier - Grand Rapids, Michigan 2001
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