Duplx 2205 vs XM-19 (nitronic 50)

[Johnwoo1991]

Is 2205 duplex (uns s31803) harder to machine than austenitic satinless steel xm-19 (uns s20910)? Are they pretty much equal for corrosion resistance?

 

[EdStainless]

Are they both annealed?
If so then I would suspect that 2205 will machine better than Nit50.
The Nitronic will work harden a lot in machining which makes life difficult.
2205 has noticeably better pitting resistance than Nit50.
We are looking at a PREn of about 31.5 for Nit50 and 34 for 2205.

 

[Johnwoo1991]

Are they both annealed?
If so then I would suspect that 2205 will machine better than Nit50.
The Nitronic will work harden a lot in machining which makes life difficult.
2205 has noticeably better pitting resistance than Nit50.
We are looking at a PREn of about 31.5 for Nit50 and 34 for 2205.

Yes, both annealed. I assume that in the "as rolled" condition, or the strain hardened condition (as per Astm A479) machinability could be even worse for xm-19.

Would you consider superduplex grades such as F55 and F53 on the par with standard duplex 2205 grade as for machinability or worse due to higher nickel and molybdenum content?

 

[EdStainless]

Actually it should machine better if it was harder.
It would work harden less when being machined.
But it take a lot of hp to cut this material.