I am a mechanical engineering co-op student currently working for Syncrude in Fort McMurray, Alberta.

Today we had a presentation from a company that makes gear boxes for industrial uses. During the presentation the presenter mentioned that they no longer use nitride coating because they found that the nitride wouldn't stay in the surface of the metal for more than 1 year. They were touting carbide coating instead.

I was just wondering if the gears in the transmission are nitride coated and if they are has anybody done any tests on the coating after a certain running time?

The guy doing the presentation said he would have his materials engineer contact me as I had quite a few question about this. Any input from here would be great.

Thank you,
Kala

Correct me if I am wrong, maybe things have progressed in the last few years that I haven't kept up with, but carbide coating would be ON TOP of the surface of the existing metal. This has always existed as an option, we had a little hand held gadget for doing this even when I served my apprenticeship. It was then very time consuming, as each application covered an area maybe 1/16" diameter. I would compare this more to like a hard chrome plating type of thing, where you are ADDING to the existing metal. Nitriding, I believe, is a process where they don't add to or remove metal, but change the characteristics of the outer skin of the existing metal. I am not sure it is fair to compare the two processes.
Also, I know for a fact I wouldn't want a broken off piece of carbide making it's way around my transmission