Alloy 20 shaft-stress relieve

We always preferred controlled stress relief rather than what may occur after assembly of the equipment and when it's in use; yes.

Alloy 20 or Carpenter 20 as many people know it will work harden as you machine it. Since it would take a lot more HP to machine or cold work a shaft one should anneal it first before starting. Depending on the amount of material that is removed an additional annealing may be required prior to the final cut.

Since many of the uses are for service in a Corrosive environment you really don't want a shaft that already goes into service with built up or locked in stresses. It would seem logical that stress relieving after the machining operation may well be necessary as well as long as dimensional stability can be maintained.