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EN Nickel delaminating


June 2, 2017

Q. We are plating EN medium phos approx. 25 microns onto aluminium followed by 0.5 - 1 micron of soft gold all over. We are getting the EN delaminating from itself; and on a tape test, the gold comes off with Ni attached but does not leave a bare area of Al, but a Ni plated area.
How can the Ni delaminate from itself? Any thoughts would be appreciated.

Steve Britton
plating shop - Honiton, Devon, England
  ^- Privately contact this inquirer -^


June 2017

A. Hi Steve. And you're sure nobody pulled these parts out to measure them or change a filter or replenish, and then put them back after they became passive?

Regards,

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


June 2, 2017

Q. Sadly I am sure of this. We repeated the process and got the same result.

Steve Britton [returning]
plating shop - Honiton, Devon, England


June 7, 2017

A. Did you make a replenishment or ammonia add, or potentially have a temperature swing while these parts were plating? Large swing in plating rate from a parameter change can cause Ni delamination from itself, especially when put under stress later (such as the soft gold layer).

Jameson Grout
Litron, Inc - Agawam, Massachusetts, USA


June 14, 2017

thumbs up sign Thanks Jameson, I will look into this and see if this is a possible cause

Steve Britton
- Honiton, Devon,England

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