EN 1.4449 (X3CrNiMo18-12-3) Stainless Steel
EN 1.4449 stainless steel is an austenitic stainless steel formulated for primary forming into wrought products. Cited properties are appropriate for the solution annealed (AT) condition. 1.4449 is the EN numeric designation for this material. X3CrNiMo18-12-3 is the EN chemical designation.
It has a moderately high ductility among the wrought austenitic stainless steels in the database.
The graph bars on the material properties cards below compare EN 1.4449 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
Elastic (Young's, Tensile) Modulus
200 GPa 29 x 106 psi
Elongation at Break
48 %
Fatigue Strength
240 MPa 35 x 103 psi
Impact Strength: V-Notched Charpy
91 J 67 ft-lb
Poisson's Ratio
0.28
Shear Modulus
78 GPa 11 x 106 psi
Shear Strength
440 MPa 64 x 103 psi
Tensile Strength: Ultimate (UTS)
620 MPa 90 x 103 psi
Tensile Strength: Yield (Proof)
250 MPa 36 x 103 psi
Thermal Properties
Latent Heat of Fusion
290 J/g
Maximum Temperature: Corrosion
410 °C 780 °F
Maximum Temperature: Mechanical
960 °C 1760 °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
3.9 kg CO2/kg material
Embodied Energy
54 MJ/kg 23 x 103 BTU/lb
Embodied Water
150 L/kg 18 gal/lb
Common Calculations
PREN (Pitting Resistance)
27
Resilience: Ultimate (Unit Rupture Work)
240 MJ/m3
Resilience: Unit (Modulus of Resilience)
160 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
22 points
Strength to Weight: Bending
20 points
Thermal Diffusivity
4.0 mm2/s
Thermal Shock Resistance
14 points
Alloy Composition
Among wrought stainless steels, the composition of EN 1.4449 stainless steel is notable for including copper (Cu) and containing a comparatively high amount of nickel (Ni). Copper is used to improve resistance to acids, and to improve formability. 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 | 62.4 to 69.3 | |
| Cr | 17 to 18.2 | |
| Ni | 11.5 to 12.5 | |
| Mo | 2.3 to 2.8 | |
| Mn | 0 to 2.0 | |
| Si | 0 to 1.0 | |
| Cu | 0 to 1.0 | |
| N | 0 to 0.080 | |
| P | 0 to 0.045 | |
| C | 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 10222-5: Steel forgings for pressure purposes - Part 5: Martensitic, austenitic and austenitic-ferritic stainless steels
Metallic Materials: Physical, Mechanical, and Corrosion Properties, Philip A. Schweitzer, 2003
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