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Long term effects of cadmium plated steel wire?

We have a large amount of 1/32" dia. high carbon steel spring wire (carbon ~ 0.91%...ASTM A228) that has been cadmium plated per AMSQQP416, Type II, Class 2. This wire has been sitting in storage for over 20-years. What effect, if any, would the cadmium plating have on the steel over time? Should I notice a reduction in wire strength and/or fatigue? Theoretical as well as practical responses would be appreciated.

Marc Pepi
US Army - Aberdeen Proving Ground, Maryland
1999

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Coincidentally, I happened to have lunch yesterday with a retired chrome plating expert who related to me something that I had never heard of. It seems that when they used to do chrome plating of large heated rolls they discovered that there was no way to completely hydrogen relieve them. On the most difficult steam heated rolls, no matter what you did in terms of baking, even 2 weeks or more at 250-280 °F, if you plastic coated them the hydrogen would still come out an cause a bubble. Repair the bubble and it would reform. There was only one real cure for the problem: aging for a year before coating!

So I would surmise that after 20 years of aging, any concern for hydrogen embrittlement is over.

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

That does not mean that there was no damage. It would be a relatively simple to do some tensile strength testing on it and see if it is suitable for your purpose. I would also unroll a big part of the spool to see what corrosion might have take place down on the innards of the spool.

James Watts
- Navarre, Florida
1999