Metal finishing Q&As since 1989

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Electroless Nickel and Oxygen

We are considering high Phosphorous electroless nickel coating for an Oxygen system.
Some platers have reservations about EN in pure Oxygen.
I would appreciate any advice.
If EN is not applicable what other low friction coating should be used for mass production shaft in a medical device.

Ariel Ring
- Israel
2005

Pure Oxygen is not the same thing as an oxidizer, but in certain situations it may behave in a similar way. So, it would be logic to use a coating that resists oxidizing agents better. I would say chrome is better than nickel for your application.

Guillermo Marrufo
Monterrey, NL, Mexico
2005

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2005

Oxygen will not attack EN at ambient temperature. EN is commonly used for pressurized gas applications in the USA.

However, your platers may be afraid that the coating will flake off and damage the oxygen system. EN does require careful pretreatment to ensure good adhesion.

Ron Duncan [deceased]
- LaVergne, Tennessee
It is our sad duty to note Ron's passing on Dec. 15, 2006. A brief obituary opens Episode 13 of our Podcast.

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2005

Ron, you are correct, one of the Chemical Engineers we use think that Nickel particles might occur, though it is rotating against Aluminum at maximum ambient temperature of 50C (122F).
Guillermo, is it possible to use Chrome, (would that be hexavalent Chrome?) in a non-invasive medical device? With the porous nature of Chrome plating, we are concerned that rust might occur on the 1040 shaft.
Thank you both for your input.

Ariel Ring
- Israel

Rust (penetration of the plate) is always a possibility when the substrate is carbon steel especially if the environment is O2. But it can be aleviated by an under layer of electrolytic nickel. I don't know if chrome is banned for this particular application. And yes, I was talking about hex chrome.

Guillermo Marrufo
Monterrey, NL, Mexico
2005