Alloy AF932N (UNS S31010) is the latest evolution of high nitrogen austenitic stainless steels.
It contains nitrogen in the range 0.8-0.9 % and has minimum 48 Pitting Resistance Equivalent Number (PREN).
This alloy is produced by air melting followed by AOD (Argon-Oxygen-Decarburization) refining in a vessel of 70 tons capacity, thus providing ingots up to 25 tons from which components up to 800 mm (31.5 in.) thickness can be manufactured.
AF932N has excellent combination of mechanical properties and corrosion resistance even on large sections, thus providing a very attractive solution for widespread applications and offering a valid alternative to annealed and solution annealed Ni alloys as well as duplex and super duplex materials.
AF932N is a highly alloyed austenitic stainless steel type 3b as defined by NACE MR0175/ISO 15156-3 (PREN > 40). Accordingly, it can be used for any equipment or components within the environmental limits of Table A.8, for gas lift service as per table A.10 and for instrument tubing, control-line tubing, compression fittings and surface and downhole screen devices as per Table A.11 of NACE MR0175/ISO 15156-3.
AF932N is being balloted for inclusion in ASTM A276 – Standard Specification for Stainless Steel Bars and Shapes and ASTM A479 – Standard Specification for Stainless Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels.