EN 1.4401 (X5CrNiMo17-12-2) Stainless Steel
EN 1.4401 stainless steel is an austenitic stainless steel formulated for primary forming into wrought products. 1.4401 is the EN numeric designation for this material. X5CrNiMo17-12-2 is the EN chemical designation.
This material is well established: the Further Reading section below cites a number of published standards, and that list is not necessarily exhaustive.
The properties of EN 1.4401 stainless steel include three common variations. This page shows summary ranges across all of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare EN 1.4401 stainless steel to: wrought austenitic 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
Brinell Hardness
190 to 270
Elastic (Young's, Tensile) Modulus
200 GPa 29 x 106 psi
Elongation at Break
14 to 40 %
Fatigue Strength
200 to 320 MPa 29 to 47 x 103 psi
Impact Strength: V-Notched Charpy
91 to 94 J 67 to 69 ft-lb
Poisson's Ratio
0.28
Shear Modulus
78 GPa 11 x 106 psi
Shear Strength
410 to 550 MPa 60 to 79 x 103 psi
Tensile Strength: Ultimate (UTS)
600 to 900 MPa 87 to 130 x 103 psi
Tensile Strength: Yield (Proof)
230 to 570 MPa 33 to 82 x 103 psi
Thermal Properties
Latent Heat of Fusion
290 J/g
Maximum Temperature: Corrosion
410 °C 770 °F
Maximum Temperature: Mechanical
950 °C 1740 °F
Melting Completion (Liquidus)
1440 °C 2630 °F
Melting Onset (Solidus)
1400 °C 2550 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
15 W/m-K 8.7 BTU/h-ft-°F
Thermal Expansion
16 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.3 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.6 % IACS
Otherwise Unclassified Properties
Base Metal Price
19 % relative
Density
7.9 g/cm3 490 lb/ft3
Embodied Carbon
3.8 kg CO2/kg material
Embodied Energy
52 MJ/kg 22 x 103 BTU/lb
Embodied Water
150 L/kg 18 gal/lb
Common Calculations
PREN (Pitting Resistance)
26
Resilience: Ultimate (Unit Rupture Work)
110 to 190 MJ/m3
Resilience: Unit (Modulus of Resilience)
130 to 800 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
21 to 32 points
Strength to Weight: Bending
20 to 26 points
Thermal Diffusivity
4.0 mm2/s
Thermal Shock Resistance
13 to 20 points
Alloy Composition
Among wrought stainless steels, the composition of EN 1.4401 stainless steel is notable for containing comparatively high amounts of nickel (Ni) and chromium (Cr). Nickel is primarily used to achieve a specific microstructure. In addition, it has a beneficial effect on mechanical properties and certain types of corrosion. Chromium is the defining alloying element of stainless steel. Higher chromium content imparts additional corrosion resistance.
| Fe | 62.8 to 71.5 | |
| Cr | 16.5 to 18.5 | |
| Ni | 10 to 13 | |
| Mo | 2.0 to 2.5 | |
| Mn | 0 to 2.0 | |
| Si | 0 to 1.0 | |
| N | 0 to 0.1 | |
| C | 0 to 0.070 | |
| P | 0 to 0.045 | |
| S | 0 to 0.015 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
EN 10222-5: Steel forgings for pressure purposes - Part 5: Martensitic, austenitic and austenitic-ferritic stainless steels
EN 10272: Stainless steel bars for pressure purposes
EN 10250-4: Open die steel forgings for general engineering purposes - Part 4: Stainless steels
EN 10269: Steels and nickel alloys for fasteners with specified elevated and/or low temperature properties
EN 10088-3: Stainless steels - Part 3: Technical delivery conditions for semi-finished products, bars, rods, wire, sections and bright products of corrosion resisting steels for general purposes
EN 10088-1: Stainless steels - Part 1: List of stainless steels
Corrosion of Austenitic Stainless Steels: Mechanism, Mitigation and Monitoring, H. S. Khatak and B. Raj (editors), 2002
Austenitic Stainless Steels: Microstructure and Mechanical Properties, P. Marshall, 1984
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