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Corrosion treatment which won't change shaft dimensions

We have been using stainless for a 1" shaft for a hinge pin purely for corrosion resistance. I'd like to start using a alloy carbon steel like "Stressproof" for additional strength and lower cost. We would need it treated somehow to prevent rust. Whatever it is cannot change the dimensions of the piece though. Ideas?

Jim Shrake
Manufacturer - Houston, Texas
2004

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Corrosion resistance and dimensional changes are issues that work along a continuum rather than being go/no-go things, Jim. But a bit of corrosion resistance can be gotten from black oxide & oil with a dimensional change measured in millionths of an inch. Zinc plating is more corrosion resistant but would need to be a minimum of about 0.0002 thick, the thicker the better.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

Thanks, I did a little more research on the thickness of Zinc plating and was surprised to find out how thin it actually is. It looks like it would work. This plating will go on a 1" Stressproof (1144) steel hinge shaft which sees only occasional 90 deg rotations (a few a day). It will be enclosed, but not completely sealed and will be outdoors. What type of plating would you recommend. Cost is a concern, so I don't want anything exotic. Zinc or Yellow zinc would be great if appropriate.

Jim Shrake
- Houston, Texas USA
2004

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Zinc is not an ideal bearing surface, but is nonetheless frequently used on hinges and hinge pins, the internal moving parts of door handles, etc., so it might be okay. But tin-zinc would offer similar or better corrosion resistance and lubricity more suited to a pin like this.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004