"45N22CrMo" is Industeel/Aperam's descriptive shorthand for the base Uranus 45N grade — the name literally spells out the alloy content that defines it: roughly 22% chromium with a molybdenum addition, on the same 2205-family duplex platform as Uranus 45N+ (also stocked by FM Carbide). This is not a separate alloy family; it's the same UNS S31803 chemistry, the same EN 1.4462 registration, and the same DIN X2CrNiMoN22-5-3 designation as 45N+. The distinction between the two Uranus 45N variants is a corrosion-guarantee tier, not a different base metal: standard Uranus 45N (this page) runs a typical PREN (pitting resistance equivalent) of roughly 33-34, while Uranus 45N+ is produced toward the alloy-rich end of the same specification window to guarantee a minimum PREN of 36.

For shop-floor purposes, that difference is metallurgically real but mechanically inconsequential — both variants share the same roughly 50/50 austenite-ferrite duplex microstructure, the same near-double yield strength over 316L, and the same chloride pitting and stress-corrosion-cracking resistance that makes 2205-family duplex the default choice for offshore equipment, pressure vessels, desalination plant hardware, and chemical tankers. If you're deciding between the two Uranus 45N pages on this site, the choice comes down to which PREN guarantee your specification calls for; the machining approach below applies equally to both.

Because Uranus 45N22CrMo shares its microstructure and alloy content with the rest of the 2205 family, it machines the same way: a dual-phase structure where the austenite fraction work-hardens moderately and the ferrite fraction — harder and stiffer, but largely immune to work hardening — drives up cutting forces and edge temperature well beyond what a straight austenitic grade like 316 produces. Both phases have to be sheared cleanly on every pass, so tool rigidity and edge support carry as much weight as sharpness in getting consistent results.

A tough, wear-resistant coated carbide grade generally outperforms an aggressive, fine-honed edge on this alloy — the priority is surviving sustained mechanical load and heat rather than minimizing work hardening the way you would on 304 or 316. Coolant is important given the alloy's modest thermal conductivity, and a rigid, low-deflection setup remains the single biggest factor in tool life, since chatter and deflection show up as chipped edges on duplex stainless faster than on standard austenitic grades.