No passwords, No popups, No cost, No AI
we earn from your eBay & Amazon purchases

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


  pub
  The authoritative public forum
  for Metal Finishing since 1989

-----

Nickel plates okay in one barrel but not another

none
adv.
this text gets replaced with bannerText
spacer gets replaced with bannerImages

Q. I am doing a project with Nickel on Nickel plating using sulfamate bath and 10V. First experiment, I got good result. Then I used slightly different barrel type, with same condition as in the first experiment, and there is no nickel at all on my nickel substrate. I have tried to change the net screen but still no nickel deposited.
all samples are same material in same size and wash in sulfuric acid before plating.

Anna Hamilton
- Taiwan
March 13, 2023



nickel book
The Sulfamate Nickel How-To Guide

by David Crotty, PhD & Robert Probert

A. Hi Anna.
Washing in sulfuric acid is not sufficient activation for nickel substrates, but I don't think you've given us any data from which to make conjectures regarding what went wrong. But what was the amperage and time in the first barrel and the amperage and time in the second barrel?

What is your experiment about, and what is the input data and output data? Thanks. Regards,

ted_yosem
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey


Q. Hi!
The experiment is for capacitor nickel termination where I connect the nickel electrodes with nickel by electrodeposition. So the nickel is supposed to be deposited on the nickel electrode. but the problem is when I used the first barrel, nickel deposited with no problem, but no nickel at all deposited with second barrel with the same set up. Both barrels use 10V, 5-6A, 50 °C, pH 3.5-4, for an hour.

I put the capacitors in the barrel with Fe balls and Zr balls (ratio 5:1) as the medium. The first barrel and second barrel have same volume. But the first barrel has wider net window than the second one. Do you think it affects the result?

61527-1a   61527-1b  

For the sulfuric acid wash, I was only thinking it is for cleaning the substrate only. What acid wash do you recommend for activation?

Anna Hamilton [returning]
student - Taiwan
March 14, 2023


A. Hi again Anna.
The reason I inquired about the amperage is that if you are consuming amperage it has to do something! As Faraday's Law tells us, when you pump all those electrons from the anode to the cathode, some ionic reaction is forced to occur to balance them. Ideally what happens is that positively charged nickel ions migrate to the cathode, encounter those electrons, and are reduced to metal atoms on the capacitors (or on the fill). If metal is not plating out, the electrons must steal hydrogen from the solution, which should result in a large amount of hydrogen gas evolving, and a sharp rise in pH due to the OH- ions left behind.

Understanding Faraday's Law, and that all those electrons have to do something, should help you get a handle on what is going on. If 5 Amps if flowing for an hour it's doing something, not nothing :-)

But sure, too small a mesh can interfere with current flow, solution flow, and maybe even ion flow and cause lots of problems. To a certain extent electroplating science is still empirical rather than fully based on first principles -- i.e., some things work, other things don't work, even if we don't understand everything there is to know about every flow gradient. And your second barrel apparently doesn't work :-)

Alkali rather than acid is usually used for cleaning, although I'm not sure if your capacitors are alkali-resistant. Usually, old nickel must be activated with a Wood's Nickel Strike or another specialty process.
Luck & Regards,

ted_yosem
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey


thumbs up sign Thank you for the explanation. I will just fix the first barrel and use it :D

40 minutes immersing in ammonia this on eBay or Amazon [affil links] will oxidize my capacitor; I shall find the suitable base solution for washing my capacitors.

Anna Hamilton [returning]
student - Taiwan




(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"