Metal Finishing Guide Book

2011-2012 Surface Finishing Guidebook

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Problem Cloudy deposit MCD or HCD Possible Cause 1. Low leveler 2. Low pH 3. High control agent 4. High STEP Additive 5. Organic contamination 6. Metallic contamination (e.g., Fe, Si, Al, Cr+3 7. Low agitation ) How to Correct 1. Increase concentration of leveler 2. Adjust pH upward 3. Reduce control agent concentration (carbon filter) 4. Temporarily discontinue additions 5. Carbon treatment 6. High pH + carbon treatment 7. Increase agitation Cloudy deposit LCD Area 1. Low leveler 2. Low pH Dull deposit LCD Area Poor leveling 1. Metallic contamination 1. Low leveler 2. Low control agent 3. Low pH 4. High STEP additive 5. Low agitation Poor ductility 1. High Leveler 2. Low control agent 3. High pH 4. Metallic contamination (e.g., Zn, Pb, Cd) 5. Organic contamination Burning 1. Low nickel salts/boric acid 2. High CD 3. Low temperature 4. Low agitation 5. Chromate contamination 6. Metallic contamination Skip plating 1. High leveler 2. Low control agent ) 3. Metallic contamination (e.g., Pb, Zn, Cd, Cr+6 1. Add nickel salts/boric acid 2. Reduce CD 3. Adjust temperature 4. Increase agitation rate 5. High CD "dummy" + high pH treatment* 6. High pH + carbon treatment 1. "Dummy" solution at 4–5 ASF 2. Add control agent 3. "Dummy" solution at 4–5 ASF Semibright Nickel–Non-Coumarin: Panels are usually plated at 2 amps for 5 minutes on steel panels. 1. Adjust leveler concentration 2. Adjust pH 1. "Dummy" solution at 4–5 ASF 1. Add leveler 2. Add control agent 3. Adjust pH 4. Temporarily discontinue additions 5. Adjust agitation 1. Reduce leveler concentration 2. Add control agent 3. Adjust pH 4. "Dummy" solution at 4–5 ASF 5. Carbon treatment 468

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