Ko te 254 SMO (UNS S31254) he kowiri tira austenitic e hototahi ana ki ētahi atu kowiri tira austenitic, ā, kua hangaia ki ngā taumata tiketike o te chromium, te molybdenum, me te hauota mō te ātete nui ki te waikura o te rua me te kapiti. Ko tēnei koranu he koranu chromium-molydenum-nickel me te hauota tonu hei huānga tāpiri; ko te hanganga tata ko: Cr 20%–22%, Mo 6%–7%, Ni 18%–20%, me te hauota e whakanui ana i tōna kaha me te ātete ki te waikura, inā koa i roto i ngā taiao e mau ana te chloride pēnei i te wai moana, te mahi i roto i te pepa, te penupenu, me ngā ahumahi matū.
Taumata Ngongo:S31254, 254 SMO, EN 1.4547, UNS S31254