EN 1.4951 (X6CrNi25-20) Stainless Steel
EN 1.4951 stainless steel is an austenitic stainless steel formulated for primary forming into wrought products. Cited properties are appropriate for the solution annealed (AT) condition. 1.4951 is the EN numeric designation for this material. X6CrNi25-20 is the EN chemical designation.
It has a moderately high base cost among wrought austenitic stainless steels. In addition, it has a moderately high embodied energy and a moderately low ductility.
The graph bars on the material properties cards below compare EN 1.4951 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
170
Elastic (Young's, Tensile) Modulus
200 GPa 29 x 106 psi
Elongation at Break
38 %
Fatigue Strength
190 MPa 27 x 103 psi
Impact Strength: V-Notched Charpy
98 J 72 ft-lb
Poisson's Ratio
0.27
Shear Modulus
79 GPa 11 x 106 psi
Shear Strength
430 MPa 62 x 103 psi
Tensile Strength: Ultimate (UTS)
630 MPa 91 x 103 psi
Tensile Strength: Yield (Proof)
220 MPa 32 x 103 psi
Thermal Properties
Latent Heat of Fusion
300 J/g
Maximum Temperature: Corrosion
450 °C 830 °F
Maximum Temperature: Mechanical
1100 °C 2010 °F
Melting Completion (Liquidus)
1410 °C 2560 °F
Melting Onset (Solidus)
1360 °C 2480 °F
Specific Heat Capacity
480 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
15 W/m-K 8.5 BTU/h-ft-°F
Thermal Expansion
16 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.1 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.4 % IACS
Otherwise Unclassified Properties
Base Metal Price
25 % relative
Density
7.9 g/cm3 490 lb/ft3
Embodied Carbon
4.3 kg CO2/kg material
Embodied Energy
61 MJ/kg 26 x 103 BTU/lb
Embodied Water
190 L/kg 23 gal/lb
Common Calculations
PREN (Pitting Resistance)
26
Resilience: Ultimate (Unit Rupture Work)
190 MJ/m3
Resilience: Unit (Modulus of Resilience)
130 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
22 points
Strength to Weight: Bending
21 points
Thermal Diffusivity
3.9 mm2/s
Thermal Shock Resistance
14 points
Alloy Composition
Among wrought stainless steels, the composition of EN 1.4951 stainless steel is notable for containing comparatively high amounts of chromium (Cr) and nickel (Ni). Chromium is the defining alloying element of stainless steel. Higher chromium content imparts additional corrosion resistance. Nickel is primarily used to achieve a specific microstructure. In addition, it has a beneficial effect on mechanical properties and certain types of corrosion.
| Fe | 49.1 to 57 | |
| Cr | 24 to 26 | |
| Ni | 19 to 22 | |
| Mn | 0 to 2.0 | |
| Si | 0 to 0.7 | |
| C | 0.040 to 0.080 | |
| N | 0 to 0.1 | |
| P | 0 to 0.035 | |
| S | 0 to 0.015 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
EN 10272: Stainless steel bars for pressure purposes
EN 10269: Steels and nickel alloys for fasteners with specified elevated and/or low temperature properties
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