Alternative to Nitrided 20MnCr5

[andrepaiva]

Good day everybody,

I've been assigned to a project of a spindle where i need to find a replacer to nitrided 20MnCr5.

The current process:
pre machining of the spindle; quenching and tempering to obtain 25~29 HRc; final machining; surface nitriding (0,3mm) to obtain >650Hv; griding.

My question is if you think AISI 4140 with induction surface hardening could be a alternative to the current process, since we have it with 25~30 HRc, and under hardening conditions ranges from 55 to 60 HRc.

Sorry about the bad inglish, and thanks for any reply.
André

 

[dbooker630]

We have made conversions from a carburized to an induction hardened process using similar materials. You may need to validate the change with some type of fatigue testing based on the expected loading your spindle will see in service.

 

[TVP]

I agree with dbooker630. Do you have the ability to test the spindle under realistic conditions?

 

[andrepaiva]

Yes i have, but i need to be sure that it is possible to achieve the same condition with the AISI 4140. This because i'll need to manufacture a specific coil in order to properly harden the spindle after its machining.
Right now i'm testing round samples with 40mm diameter to verify if they can be hardened up to ~57HRc with the ideal depth in the induction hardening machine.

André