The properties of duplex stainless steels are achieved with overall lower alloy content than similar-performing super-austenitic grades, making their use cost-effective for many applications. Duplex grades are characterized into groups based on their alloy content and corrosion resistance.
| Alloy | BÖHLER brand | WstNo. | UNS | ISO | AMS | ASTM | Others |
| Super Duplex | A913 | 1.4410 | S32750 | X2CrNiMoN25-7-4 | – | – | F53 |
| Duplex | A903 | 1.4462 | S31803, S32205 | X2CrNiMoN22-5-3 | – | – | F51, STN: 17 381 |
| Super Duplex | A911 | 1.4501 | S32760 | X2CrNiMoCuWN25-7-4 | – | – | F55 |
| Ferralium 255 | A923 | 1.4507 | S32550 | X2CrNiMoCuN25-6-3 | F61, F255 |