Originally Posted by
BigChief
Just as a point of interest, you can restore case hardening of parts like this by simply glowing the part with a torch and quenching in water. Manufacturers use oil hardening steel so they can machine parts in a soft state then they are heated in a furnace and quenched in oil. Glowing with a torch and quenching in water isn't as accurate but still case hardens parts surprisingly well. So if you have an axle or cone that is difficult to replace, it would be possible to resurface it on a lathe with radius stones and lapping polish then re heat treat it to a reasonable case hardness.
You have a poor understanding of case hardening.
It involves "baking" the steel part in a bed of carbon so that some carbon "transfers" to the steel. The CARBON is the key.
Since this is an
extremely thin surface layer, any grinding penetrates through it.
The point of case hardening is to have a hard surface without the rest of the part being as brittle.
It's the CARBON in the steel that contributes to its "heat treatability".
Without any carbon, they call it IRON.