Carbon and low-alloy steels
Iron-carbon steels, with or without chromium, molybdenum, nickel and vanadium, for flanges, shafts, gears and pressure forgings: from A105 for piping to the Cr-Mo F22 and F91 used in refineries.
Carbon and low-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 |
| 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 |
| 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 A105 – Forged carbon steel for pipingCarbon steel · Carbon-manganese steel for forged flanges, fittings and valves | K03504 | ≈ P250GH | Bar, Pipe, Forging and flange, Fitting |
| 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 |
| ASTM A522 Type I – 9% Ni steelAlloy steel · Forged 9% nickel ferritic steel for cryogenic service down to −196 °C | K81340 | X8Ni9 | Bar, Plate, Pipe, Forging and flange, Fitting |
| ASTM A694 F65 – High-yield steel forgingCarbon steel · Forged carbon steel for high-pressure pipeline flanges and fittings | — | — | Pipe, Forging and flange, Fitting |
| 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.
Which alloy resists each environment
Indicative summary from the corrosive media calculator, under typical conditions. For your medium, concentration and temperature, use the calculator.
| Material | Fresh water (200 ppm Cl⁻, 25 °C) | Seawater (20,000 ppm Cl⁻, 25 °C) | Sulfuric acid 20 %, 40 °C | Air at 800 °C |
|---|---|---|---|---|
| ASTM A105 – Forged carbon steel for piping | limited | not recommended | not recommended | not recommended |
| ASTM A182 F5 | — | — | — | not recommended |
| ASTM A182 F9 | — | — | — | not recommended |
| ASTM A182 F11 Class 2 | — | — | — | not recommended |
| ASTM A182 F22 / P22 (2¼Cr-1Mo) | — | — | — | not recommended |
| ASTM A182 F91 Type 1 | — | — | — | not recommended |
About carbon and low-alloy steels
The group covers three uses. Piping and pressure: ASTM A105 for flanges, fittings and valves. Mechanical engineering: quenched and tempered 4140 and 4340 for shafts, pins and gears, 9315 for carburizing and 8550 (34CrAlNi7-10) for nitriding. High temperature and hydrogen: the Cr-Mo grades F1, F11, F22, F5, F9 and F91, which keep creep strength in refineries and boilers. A522 Type I (9 % Ni) serves cryogenic service.
Heat treatment is what separates the applications: normalizing for A105, quenching and tempering for 4140 and 4340, normalizing and tempering for Cr-Mo. In welding, the carbon equivalent indicates the need for preheating and post-weld heat treatment.
See also
Frequently asked questions
What is the difference between carbon steel and low-alloy steel?
Carbon steel has carbon, manganese and silicon as its main elements. Low-alloy steel receives small amounts of chromium, molybdenum, nickel or vanadium to gain hardenability, toughness or high-temperature strength.
Which steel to use above 425 °C?
Carbon steel loses creep strength above about 425 °C. From there on, Cr-Mo steels take over: F11 and F22 in the intermediate ranges and F91 at the highest temperatures of boilers and refineries.