Quote:
Originally Posted by rothwem
I'm a metallurgist actually, so I can answer the heat treating questions. The answer is, "it depends"  . Really, the particular alloy and the current heat treatment are going to dictate whether you can anneal and re-harden the parts. My guess is that this is a fairly "normal" steel like a 1045 though, so I'd venture to guess that you'll be okay. With that said, one thing I'd be a little concerned about would be distortion. When you anneal a hardened part, you're taking it from martensite to austenite when its at temperature, and then back down to ferrite/pearlite at room temp. Martensite/austenite/ferrite/pearlite are all just different ways that the atoms can be arranged; temperature and temp changes alter the way that the atoms want to sit next to each other. So with all the atoms moving around, there are slight volume changes that can occur and with a non-uniform part the result can be distortion.
At the axle plant I worked at, we would do a rough turn, finish turn, heat treat, THEN grind the bearing diameters and thread the ends of the fixed joints. I suspect that some kind of finish grind might be required on your pinion gear and I'm not super familiar with the equipment that would be used to do that. We had specialized grinding wheels made for each family of part numbers but there's got to be an easier way to do it for small volume production. |
Fantastic info, fascinating. Thanks for the lesson.