For welding, in some respects 2205 is even easier than 300 series austenitic stainless (eg 316L). The weld metal itself is highly resistant to hot cracking, so the heat input does not need to be carefully limited on that account.
However you do have to pay careful attention to the heat affected zone adjacent to the weld, the primary consideration being to minimise the *total* time it spends at red heat. (To avert carbide precipitation, which grades like 316L are designed to avoid)
This means that multiple weld runs should be avoided if possible, and so should amateur welding. Weld prep should generally be machined to a carefully chosen profile with a uniform land or gap to prevent burnthrough, not offhand ground.
Preheating is inadvisable, and if multipass welding is unavoidable, the maximum temperature of the base metal between passes should be limited to 150deg C (100 deg C for superduplex)
As far as machining, it's a lot tougher than 316. Maybe as much as forty percent. It's right up there with some of the exotic nickel alloys.
The swarf in particular can be a problem, especially when turning, if you don't have a really rigid machine (even by industrial standards) with *lots* of horsepower, so you can jack up the feed rate enough to break the curly swarf up into chips. Otherwise the swarf is so gnarly and strong that it can loop over (say) a toolpost clamping screw, and wrench the toolpost out of whack (DAMHIKT) or even cause damage to the lathe.
I believe this is primarily because in duplex grades the sulphur content is kept exceptionally low for metallurgical reasons, whereas in other grades its inclusion helps promote the swarf breaking into chips.
Drilling is not too bad: it's not as prone to work-hardening as 300 series which is why the latter can be difficult to drill for the unwary. Slow going, though.
If you have lots of holes it's worth investing in an "armour piercing" drill, certainly you want at least cobalt HSS rather than conventional HSS.
Unlike 316, I wouldn't want to try drilling it with a hand drill ...
Cold Forming/bending: you'll need a stronger machine to form 2205 than 303 or 304 or 316. As a
rule of thumb, the machine would need about as much tonnage for 2205 of a given thickness as for 316 of double that thickness. Which in turn is already a significantly heavier machine than for mild
steel.
Because of the reduced elongation before break mentioned in an earlier post, you also need to increase the minimum bend radii in comparison with 3xx stainless. Maybe by 30% or so. And you'll need to allow for more springback (which means for the purposes of illustration you might have to bend it through maybe 100 degrees to end up with a 90 degree bend, in the situation when the same bend in 316 would require say 95 degrees. In practice the amount is determined by trial and error, but the tooling may not have enough angular clearance, if it's not intended for such springy material)
It is less sensitive to the relative direction of rolling grain with respect to fold lines than most other rolled plate.
It makes pretty nice castings, and you can often buy up offcuts of large engineering rounds (round bar, short ends of maybe 100mm or 150 diameter) at a surprisingly affordable rate which you can supply to the foundry as raw material. Naturally you need to pick a foundry who are experienced with casting this grade.
If my genuine Bruce
anchor ever gets irretrievably jammed I've made an accurate 3D CAD model (trickiest shape I've ever dealt with! I should have 3D scanned it, but I hate backing down) and I'd get a pattern CNC machined, or even possibly a sand mould 3D printed, and cast a replacement in 2205.
That's because the bow of my
boat, including the
anchor launching and retrieval, is designed around that anchor. And the original anchor is cast from a very strong, tough grade of manganese
steel - I think 2205 would be an eminently suitable replacement.
(Incidentally, I do not personally consider 316 suitable for an anchor used for other than overnight stays, from a
corrosion resistance standpoint. I think it's an unfortunate innovation of recent times, along with 316 anchor chain.)