EN 1.4901 (X10CrWMoVNb9-2) Stainless Steel
EN 1.4901 stainless steel is a duplex stainless steel formulated for primary forming into wrought products. Cited properties are appropriate for the normalized and tempered condition. 1.4901 is the EN numeric designation for this material. X10CrWMoVNb9-2 is the EN chemical designation.
It has a fairly low base cost among wrought duplex stainless steels. In addition, it has the highest electrical conductivity and the highest thermal conductivity.
The graph bars on the material properties cards below compare EN 1.4901 stainless steel to: wrought duplex stainless steels (top), all iron alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Elastic (Young's, Tensile) Modulus
190 GPa 28 x 106 psi
Elongation at Break
19 %
Fatigue Strength
310 MPa 45 x 103 psi
Impact Strength: V-Notched Charpy
38 J 28 ft-lb
Poisson's Ratio
0.28
Shear Modulus
76 GPa 11 x 106 psi
Shear Strength
460 MPa 66 x 103 psi
Tensile Strength: Ultimate (UTS)
740 MPa 110 x 103 psi
Tensile Strength: Yield (Proof)
490 MPa 71 x 103 psi
Thermal Properties
Latent Heat of Fusion
260 J/g
Maximum Temperature: Corrosion
380 °C 720 °F
Maximum Temperature: Mechanical
650 °C 1210 °F
Melting Completion (Liquidus)
1490 °C 2710 °F
Melting Onset (Solidus)
1450 °C 2640 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
26 W/m-K 15 BTU/h-ft-°F
Thermal Expansion
12 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
8.2 % IACS
Electrical Conductivity: Equal Weight (Specific)
9.3 % IACS
Otherwise Unclassified Properties
Base Metal Price
11 % relative
Density
7.9 g/cm3 500 lb/ft3
Embodied Carbon
2.8 kg CO2/kg material
Embodied Energy
40 MJ/kg 17 x 103 BTU/lb
Embodied Water
89 L/kg 11 gal/lb
Common Calculations
PREN (Pitting Resistance)
14
Resilience: Ultimate (Unit Rupture Work)
120 MJ/m3
Resilience: Unit (Modulus of Resilience)
620 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
26 points
Strength to Weight: Bending
23 points
Thermal Diffusivity
6.9 mm2/s
Thermal Shock Resistance
23 points
Alloy Composition
Among wrought stainless steels, the composition of EN 1.4901 stainless steel is notable for including zirconium (Zr) and boron (B). Zirconium is used to improve ductility and oxidation resistance. Boron is used to improve hardenability. It has a substantial effect when added in even tiny amounts. It can also facilitate sintering.
| Fe | 85.8 to 89.1 | |
| Cr | 8.5 to 9.5 | |
| W | 1.5 to 2.0 | |
| Mo | 0.3 to 0.6 | |
| Mn | 0.3 to 0.6 | |
| Si | 0 to 0.5 | |
| V | 0.15 to 0.25 | |
| Ni | 0 to 0.4 | |
| C | 0.070 to 0.13 | |
| Nb | 0.040 to 0.090 | |
| N | 0.030 to 0.070 | |
| P | 0 to 0.020 | |
| Al | 0 to 0.020 | |
| S | 0 to 0.010 | |
| Ti | 0 to 0.010 | |
| Zr | 0 to 0.010 | |
| B | 0.0010 to 0.0060 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
EN 10216-2: Seamless steel tubes for pressure purposes - Technical delivery conditions - Part 2: Non-alloy and alloy steel tubes with specified elevated temperature properties
Pressure Vessels: External Pressure Technology, 2nd ed., Carl T. F. Ross, 2011
Corrosion of Stainless Steels, A. John Sedriks, 1996
Advances in Stainless Steels, Baldev Raj et al. (editors), 2010
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015