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Ni and Cr Plated Mild Steel Parts

We found Nickel in Cr plated Mild Steel parts by XRF. Is it normal? The parts with Ni and Cr on the surface show poor adhesion to TiN coating. Could anybody give us help on this? Thanks in advance.

Sheron Wen
- Minnesota, USA
2002

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It depends on why they were chrome plated. Decorative "chrome plating" is actually comprised on a couple of thousandths of an inch of nickel followed by one hundreth that thickness of chrome. If you don't know the history of the sheets it is very difficult to know why the TiN isn't sticking. But why would you put chrome under TiN anyway? Nickel, yes, to avoid porosity.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2002

I don't know why the customer does this. It looks like a lot of industry company like this way. They do Cr plating first for good corrosion resistance and then coat over with TiN for good wear resistance. But sometimes it is difficult to get good TiN coating adhesion on Cr plated parts and it is hard to tell whether Cr plating spalls or TiN flakes.

Sheron Wen
- Minnesota
2002