Summary for nickel plating pits Discussion
Nickel plating pits and stain marks are discussed as possible process or substrate issues rather than a clearly identified plating defect. In the 2021 question, parts plated to AMSQQN290 showed surface conditions seen with a borescope, and the plater said nothing was open to base metal. Popatbhai B. Patel asked first about the magnification and suggested the small pits could be caused by low boric acid; he also noted that if boric acid was added during plating, a similar appearance can occur, though the photos made it hard to tell whether the pits were above or below the deposit. He said the larger affected area might be a cleanliness problem before plating or irregularities in the substrate made more visible by lighting. The thread also includes an older related answer from Milton Franklin, who said he would not accept surface contamination or discoloration and would first check final rinsing, suspecting hard-water chalk deposits or rinse contamination.
Q. I have parts that were nickel plated per AMSQQN290.
During visual inspection using a borescope several surface conditions were observed.
The plating house was unable to give me a satisfactory answer as to what we are seeing. According to the plater, there are no defects that are open to the base material.
There are other conditions that appear to be pits, stains, ???
James Campbell
– Santa Fe Springs California USA
? Your plating process is not in detail. What is your base metal, do you have semi-bright nickel and bright nickel?
Popatbhai B. Patel
electroplating consultant – Roseville, Michigan
February 14, 2021
What magnification are the images?
The small pits could be due to low boric acid.
If the operator/lab tech made a boric addition while plating the same effect can be seen (hard to tell from the images if the pits are below or above the deposit surface).
The larger defect area are hard to diagnose; could be a cleanliness issue with the surface prior to plating; could also be irregularities in the substrate magnified by the lighting.
Jeff Marten
– Colorado Springs, Colorado
June 2, 2021
⇩ Similar, related, Q&As — oldest first ⇩
September 17, 2010
Q. Hi all,
I am using a magnet, cylinder in shape with a ID of 3 mm & height 8 mm. It is being assembled with a shaft. The magnet was plated with copper followed by Nickel. We encounter the following problems:
1. White powdery layer fully covered on the ID of the magnet, it can be easily cleaned with the cloth, does this layer formed during the plating process? Since the magnet & the shaft assembled using loctite, does this defect affect the bonding strength?
2. We also see some brown stain marks in the ID, is this acceptable in plating standard? What is the cause for this stain mark? Does this defect affect the bonding strength?
All the defects found only on the ID of the magnet, outer surface is clean from all the defects.
Appreciate your valuable advise.
Thanks
Franklin / Singapore.
Milton Franklin
Supplier Quality Engineer – Singapore
A. If I was your customer, I would not accept any surface contamination or discoloration. You give very little information about your process, but the first thing you should look at is your final rinsing. I would suspect the white powder is a chalk deposit coming from a hard water rinse. the other stains could be rinse water contamination or any one of a thousand other things. The final rinses should be with clean water, preferably hot
Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
September 20, 2010
October 8, 2010
A. Hello,
I suspect rinse water too !
Organic or mineral content of the rinse could apply a white greasy deposit on nickel. Try alkaline degreasing 30s and cathodic degreasing 30s after plating to remove deposit.
In the past, I have dark stains on nickel, it comes from acid rinse water. I remove these stains with alkaline degreasing + cathodic degreasing + nickel salt activator 2-5 min.
In any case, you have to monitoring your rinse water. Acid water is not good for rinsing.
Note : to avoid dark stains after nickel barrel plating, some plater dip in commercial citric acid
⇦ on
or
Amazon [affil link] the barrel after the final rinse.
Hope it can help you,
Nicolas
Nicolas DUTHIL
– Bordeaux, France