Metal finishing Q&As since 1989
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Why is Nickel Chrome Plating Peeling?
Q. What would be some causes for Nickel chrome to peel from an item? We are coating steel parts that are machined at a machine shop and the main area of concern is on male squares.
Mike Engelking- Elkmont, Alabama
2006
A. Mike !
You have nickel peeling problem from base metal.
I would like to check activation of base metal. You did not say if you nickel strike plate or not. Secondly what is the base metal you have for those parts? Because all different metals have different activation sequences before pre plate. After pre plate nickel (like nickel strike) then you can plate nickel chrome on it.
Popatbhai B. Patel
electroplating consultant - Roseville, Michigan
2006
A. That is a bold statement to make as it could just as easily be the nickel passivating and the chrome not sticking to the nickel. He needs to look at the underside of the chrome peel to see if he can find a tan of nickel and then to look at the peeled area of the part to see if there is nickel there. He could do a spot test on both surfaces. Then, solve the cause of the problem, substrate or nickel.
James Watts- Navarre, Florida
2006
A. In my opinion:
- improper precleaning and/or activation of substrate (plate peels from the steel substrate),
- passivation of nickel plate before entering the chrome (chrome peels from nickel),
- too much current causing burning in high current areas (edges and tips defects),
- chemical unbalance or contamination of bath.
Monterrey, NL, Mexico
2006
Plating shop blames the metal, but the nickel is sticking, just not the chrome
Q. I work for a manufacturer of packaging machinery. We have used a local chrome plating company for many years and have had few issues. However, recently we sent a large batch of steel parts for chroming, and it came back with the chrome peeling off. When I asked the plating company about it, they said it must be because the parts are made of "poor metal" and they are refusing to offer a refund (they can't rechrome the parts so we have to scrap them). We have always provided them the same steel parts (just CRS 1018 steel).
But underneath the peeling chrome I can see the nickel layer, not the bare metal. So please help me understand how it could be bad metal if the nickel layer is sticking onto that metal, but the top thin chrome layer is peeling off? Thanks for any advice so I can sound intelligent when discussing with the plating company.
vivian Woo- Los Angeles, California USA
September 16, 2014
A. Hi Vivian. You already sound intelligent discussing this :-)
I think you're right: if the nickel plating is adhering to the steel, but the chrome is peeling from the nickel plating, it sounds like the plating shop's fault.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
September 2014
A. Hi Vivian,
Peeling chrome from nickel is almost always due to the nickel layer becoming passive before the chrome plating process starts. Your plating company should recognize this as the most likely cause and investigate why it is happening instead of trying to blame the base material.
Aerospace - Yeovil, Somerset, UK
September 17, 2014
Thank you to all who responded. This website is a great resource! They chromed an equivalent batch of parts for free, although the previous batch is still all scrap. Seems like they should offer a discount to cover my scrap, but I'm tired of arguing. The more "intelligent" I sound, the angrier they are getting :-)
- Los Angeles, California USA
September 17, 2014
A. Hi Vivian,
Chrome is not sticking with Nickel because of Nickel layer passivation, plating cycle after nickel, rinses pH is too high, longer time in rinse tank makes more passivation nickel surface.
You need nickel activator and chrome predip before chrome plate.
Popatbhai B. Patel
electroplating consultant - Roseville, Michigan
December 1, 2014
Q. There are specific chemicals and procedures to strip nickel and chrome without damage to the base steel. Depending on your parts cost they could be worth trying.
Guillermo Marrufo- Monterrey Mexico
December 8, 2014
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