Search our quarter-million Q&As

Home of the finishing HOTLINE since 1989

-----

PROBLEMS FACED IN CHLORIDE ZINC PLATING

I am a electroplating chemist and handling a chloride zinc plating line, plating automotive components of castings and sheet metals. I am facing a problem of "discoloration of green passivation" after 2 or 3 days of plating. I've thoroughly given carbon, zinc dust ⇦ on eBay or Amazon [affil link] treatment for any organic/inorganic impurities. Now the solution is perfectly alright in Hull Cell ⇦ huh? test. The discoloration is coming only in green passivation and not in blue or yellow. I am following strictly the parameters recommended by the supplier of the passivations. Can any one help me in diagnosing this problem.

Thanks in advance,

Rummy Cai
- Chennai, India
2003

---

2003

Dear Rummy Cai,

The problem isn't as rummy as it sounds :). You need to start with yr plating bath. Reduce the addition of R Brightener to minimum levels and increase dosage of M to ensure total dissolution of the R in the bath. After that please rinse copiously to ensure that no brightener film remains on the part before passivation. I do hope you have a strong Nitric dip prior to Green ?

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

Sorry! Finishing.com is temporarily Read-Only.
Ted Mooney is retiring but I have several offers to take it over.
We're working hard to make sure we find it the best new home.

---

---