No passwords, No popups, No cost, No AI:
we earn from 'affiliate link' purchases, making the site possible

Home /
T.O.C.
Fun
FAQs
Good
Books
Ref.
Libr.
Adver-
tise
Help
Wanted
Current
Q&A's
Site 🔍
Search
ted_yosem
Sound technical content, curated with aloha by
Ted Mooney, P.E. RET
Pine Beach, NJ
finishing.com -- The Home Page of the Finishing Industry

  The authoritative public forum
  for Metal Finishing since 1989
  mfhotline


  -----

Cracking of plated copper alloy parts during bending




Hi,

I'm having a problem with copper alloy parts with small diameters (0.6mm) being bent at a 90 degree angle, with a bend radius of 0.6mm. The plating is copper flash, low stress nickel sulphamate, then pure gold on top (99.7%). The parts sometimes crack, and sometimes break right off. Other times, they look great. I know that the MIL specs suggest deforming before plating, but that is not an option in some cases because of the product hierarchy and assembly issues.

Any suggestions?

Paul Cabana
- Hudson, Mass, USA
2001



simultaneous replies

My guess would be that you might not have an equal thickness of nickel plating on all the parts. The parts which the thicker plating, would be the ones that have cracked plating. The ones with thinner nickel layer might be the ones that remained ok. I would check on these lines.

Mark Camilleri
- Malta



Is the plating coming off, or is the parent metal breaking? If the metal is breaking, lower the hardness or anneal after plate at a suitable temp/time for the metal and plating. This will take a higher temp than the conventional 375F used for de-embrittlement.

James Watts
- Navarre, Florida




(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully 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 might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

Finishing
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g,
& Software


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"