Alloy steels
Alloy steels are carbon steels with intentional additions of chromium, molybdenum, nickel, vanadium or aluminum to gain hardenability, hot strength or wear resistance.
Alloy steels: alloys supplied by Dustre
Forms: Bar, Pipe, Forging and flange, Casting, Plate, Fitting. Click an alloy to see standards by form, composition, properties and equivalents.
| Material | UNS | W.Nr. / EN | Forms |
|---|---|---|---|
| 300M steel (modified 4340)Alloy steel · Ultra-high-strength low-alloy steel: 4340 with silicon and vanadium | K44220 | Sem equivalente EN direto | Bar, Pipe, Forging and flange, Casting |
| 8550 steel – 34CrAlNi7-10 (W.Nr. 1.8550)Alloy steel · Cr-Al-Ni-Mo nitriding steel | Sem UNS | 1.8550 | Bar, Forging and flange |
| ASTM A182 F1Alloy steel · Forged carbon-molybdenum (C-½Mo) steel for elevated temperature | K12822 | ≈ 16Mo3 | Plate, Pipe, Forging and flange, Fitting, Casting |
| ASTM A182 F5Alloy steel · Forged 5Cr-½Mo steel for high temperature and sulfidizing media | K41545 | X16CrMo5-1 | Bar, Plate, Pipe, Forging and flange, Fitting, Casting |
| ASTM A182 F9Alloy steel · Forged 9Cr-1Mo steel for high temperature and sulfidizing media | K90941 | X11CrMo9-1 | Plate, Pipe, Forging and flange, Fitting, Casting |
| ASTM A182 F11 Class 2Alloy steel · Forged 1¼Cr-½Mo steel for steam and elevated temperature | K11572 | ≈ 13CrMo4-5 | Plate, Pipe, Forging and flange, Fitting, Casting |
| ASTM A182 F22 / P22 (2¼Cr-1Mo)Cr-Mo alloy steel · All standards by product form | K21590 | 1.7380 10CrMo9-10 | Bar, Plate, Pipe, Forging and flange, Fitting, Casting |
| ASTM A182 F91 Type 1Alloy steel · Modified 9Cr-1Mo-V-Nb ("P91") steel for creep | K90901 | X10CrMoVNb9-1 | Plate, Pipe, Forging and flange, Fitting, Casting |
| Maraging 250Alloy steel · Age-hardenable 18Ni(250) maraging steel | K92890 | 1.6359 | Bar, Plate, Forging and flange |
| SAE 4140Alloy steel · Chromium-molybdenum low-alloy steel for quenching and tempering | G41400 | 42CrMo4 | Bar, Plate, Pipe, Forging and flange |
| SAE 4340Alloy steel · High-hardenability nickel-chromium-molybdenum low-alloy steel | G43400 | ≈ 34CrNiMo6 | Bar, Plate, Pipe, Forging and flange |
| SAE 9315 – AMS 6263Alloy steel · High-hardenability Ni-Cr-Mo carburizing steel | G93150 | ≈ 15NiCr13 | Bar, Pipe, Forging and flange |
Did not find the alloy? See all materials or ask the technical team.
About alloy steels
Two uses dominate. Mechanical construction: 4140 and 4340 (Cr-Mo and Cr-Ni-Mo) for shafts, gears and pins, quenched and tempered; 8620 and 9315 for carburizing; 8550 (34CrAlNi7-10) for nitriding. High temperature and pressure: the Cr-Mo grades F11 (1¼Cr), F22 (2¼Cr), F5, F9 and F91 (9Cr-1Mo-V) for refinery flanges, fittings and vessels, resistant to creep and hydrogen attack.
Each element plays a role: chromium and molybdenum increase hardenability and hot strength; nickel gives toughness; vanadium refines the grain and holds creep strength; aluminum allows nitriding.
See also
Frequently asked questions
4140 or 4340?
4340 contains nickel and through-hardens in larger sections with more toughness; 4140 serves shafts and pins up to about 100 mm at lower cost.
What is F22 used for?
Flanges, fittings and forgings for refineries and boilers between 400 and 550 °C, where carbon steel loses strength and suffers hydrogen attack.
