-- The Home Page of the Finishing Industry

on this site
current topics
Live! From Pine Beach NJ: The world's most popular metal finishing website, and the internet's friendliest corner

topic 35620

My Nickel anodes are getting black in bright nickel tank.

adv.   carter banner


We are doing bicycle rims in semi-submerged form. We have noticed that of late the bath stops responding after 4-5 hours of working. The plating finish is dull and shows passivity. Very poor chromium reception. We have noticed that the anodes are getting black when this happens. We have tried conventional high & low pH treatments without any luck. What could be the reason.

K. Ramesh
plating shop - Mumbai-India


Very little information. Please tell us what chemistry do you have in the bath, anode-cathode ratio, chloride concentration, type of brighteners, etc.

Guillermo Marrufo
Monterrey, NL, Mexico


What is the bath composition and what should it be? Are your anodes sulphur depolarised or not? Too many questions and not enough information. It sounds like your anodes are passivating, but without more information no-one can tell. If that is the case, you may need to add chloride to the bath, but if it is a sulphamate bath that is not the best remedy.

trevor crichton
Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK


(I hope Mr. Mooney agree with me?)
Its very easy answer.But I don't understood why any body answer this question exactly.There is some reason;check your bath ph value.It must be between 3,8-4,1.If your bath ph value above 5.0 your anodes getting passivated and turns dark and some metallic contaminants getting collapse deep.So you must work between 3,8-4,1 for ph.Secondly,your boric acid value must be between 40-35 gr/lt.If your bath value under 35 gr/lt your anodes getting blackness and it turns dark.You check these.So turn us...

Alaattin Tuna
- Turkey

If you have a question in mind which seems off topic, please Search the Site

ADD a Q, A, or Comment on THIS topic START an UNRELATED topicView CURRENT HOT TOPICS

Disclaimer: It's not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices

©1995-2019, Inc., Pine Beach, NJ   -   About   -  Privacy Policy
How Google uses data when you visit this site.