EN 1.4903 (X10CrMoVNb9-1) Stainless Steel
EN 1.4903 stainless steel is a martensitic stainless steel formulated for primary forming into wrought products. 1.4903 is the EN numeric designation for this material. X10CrMoVNb9-1 is the EN chemical designation.
It has a fairly high electrical conductivity among wrought martensitic stainless steels. In addition, it can have a moderately high ductility and a fairly low tensile strength.
The properties of EN 1.4903 stainless steel include two common variations. This page shows summary ranges across both of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare EN 1.4903 stainless steel to: wrought martensitic 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
20 to 21 %
Fatigue Strength
320 to 330 MPa 46 to 48 x 103 psi
Impact Strength: V-Notched Charpy
42 to 46 J 31 to 34 ft-lb
Poisson's Ratio
0.28
Shear Modulus
75 GPa 11 x 106 psi
Shear Strength
420 MPa 61 to 62 x 103 psi
Tensile Strength: Ultimate (UTS)
670 to 680 MPa 98 to 99 x 103 psi
Tensile Strength: Yield (Proof)
500 MPa 72 to 73 x 103 psi
Thermal Properties
Latent Heat of Fusion
270 J/g
Maximum Temperature: Corrosion
380 °C 720 °F
Maximum Temperature: Mechanical
650 °C 1200 °F
Melting Completion (Liquidus)
1460 °C 2660 °F
Melting Onset (Solidus)
1420 °C 2580 °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
11 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
3.4 % IACS
Electrical Conductivity: Equal Weight (Specific)
4.0 % IACS
Otherwise Unclassified Properties
Base Metal Price
7.0 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
2.6 kg CO2/kg material
Embodied Energy
36 MJ/kg 16 x 103 BTU/lb
Embodied Water
88 L/kg 11 gal/lb
Common Calculations
PREN (Pitting Resistance)
13
Resilience: Ultimate (Unit Rupture Work)
120 to 130 MJ/m3
Resilience: Unit (Modulus of Resilience)
650 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
24 points
Strength to Weight: Bending
22 points
Thermal Diffusivity
7.0 mm2/s
Thermal Shock Resistance
23 points
Alloy Composition
Among wrought stainless steels, the composition of EN 1.4903 stainless steel is notable for including vanadium (V) and aluminum (Al). Vanadium has a strong hardening effect, but this effect is particularly sensitive to the type of tempering. Aluminum is used to improve oxidation resistance. It can also enhance the effects of heat treatment.
Fe | 87.1 to 90.5 | |
Cr | 8.0 to 9.5 | |
Mo | 0.85 to 1.1 | |
Mn | 0.3 to 0.6 | |
Si | 0 to 0.5 | |
V | 0.18 to 0.25 | |
Ni | 0 to 0.4 | |
Cu | 0 to 0.3 | |
C | 0.080 to 0.12 | |
Nb | 0.060 to 0.1 | |
N | 0.030 to 0.070 | |
Al | 0 to 0.040 | |
P | 0 to 0.025 | |
S | 0 to 0.015 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
EN 10222-2: Steel forgings for pressure purposes - Part 2: Ferritic and martensitic steels with specified elevated temperature properties
EN 10028-2: Flat products made of steels for pressure purposes - Part 2: Non-alloy and alloy steels with specified elevated temperature properties
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
EN 10302: Creep resisting steels, nickel and cobalt alloys
Machining of Stainless Steels and Super Alloys: Traditional and Nontraditional Techniques, Helmi A. Youssef, 2016
Creep-Resistant Steels, Fujio Abe et al. (editors), 2008
EN 10088-1: Stainless steels - Part 1: List of stainless steels
Welding Metallurgy of Stainless Steels, Erich Folkhard et al., 2012
Pressure Vessels: External Pressure Technology, 2nd ed., Carl T. F. Ross, 2011
Corrosion of Stainless Steels, A. John Sedriks, 1996