>i'm interested in any research or information on the long-term wearability of
>carburized parts versus induction hardened parts. specificly, carburized
>C-1019 (and any C-1018 through C-1025) versus induction hardened C-1050 (and
>any C-1045 through C-1055).
>
>
>thanks,
>jack wenger
>
Hello, Jack --
A couple of thoughts on carburizing vs. induction hardening:
* If your carburize, you can run carbon content at the surface up to
whatever you need; 0.8% carbon should be no problem. You can also get
carbon added to the entire surface of the part, except where you might
choose to stop it off, with copper plating, etc. Depth of carburizing is
controllable, but effective depth of carburizing in the range of 0.030" to
0.060" is common.
* The hardness of a martensitic case depends on the carbon content, but
there is a point of diminishing returns somewhere near 0.5% carbon.
Theoretically, the harder the better, as far as resisting wear.
* Induction hardening typically produces depths of hardening from about
0.50" to 0.10", but greater or lesser depths can be achieved. With
induction hardening, the issue may boil down to the ability to successfully
heat the surface. If the shape is complex, you may have problems.
* You'll probably want to temper the steel after either operation, just
a touch, to stabilize the structure. Something like 350F for an hour.
* If the application allows lubrication, either will work. In the
automotive business, camshafts and crankshafts are typically induction
hardened, while transmission gears are typically carburized. Shape of the
surfaces being hardened is probably the single most important factor in
making these decisions.
* If the nature of the application mandates continuing unlubricated
abrasive wear, you're into an entirely different world. I'd think about
Hadfield's manganese steel, or Stellite overlays, or AMPCO metal wear
strips. Or maybe even something soft, like rubber.
* Bottom line. Is lubrication possible? How will the shape of the
parts affect the ability to induction harden? Are there issues regarding
forging/machining/ welding that may preclude a medium carbon steel?
You've raised one of those classic cases where the best solution isn't
easily determined. I feel that the best solution in real world applications
may well be determined by factors other that which method of surface
hardening provides the better wear resistance. If you need more info,
contact me at (513) 529-2647, or E-Mail at bardesbp@muohio.edu
Hope this helps.
Bruce Bardes