EN 1.7390 (X15CrMo5-1) High-Chromium Steel
EN 1.7390 steel is an alloy steel formulated for primary forming into wrought products. Cited properties are appropriate for the normalized and tempered condition. 1.7390 is the EN numeric designation for this material. X15CrMo5-1 is the EN chemical designation.
It has a very high electrical conductivity among EN wrought alloy steels. In addition, it has a very high base cost and a moderately low thermal conductivity.
The graph bars on the material properties cards below compare EN 1.7390 steel to: EN wrought alloy 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
210
Elastic (Young's, Tensile) Modulus
190 GPa 28 x 106 psi
Elongation at Break
16 %
Fatigue Strength
310 MPa 46 x 103 psi
Impact Strength: V-Notched Charpy
46 J 34 ft-lb
Poisson's Ratio
0.29
Reduction in Area
50 %
Shear Modulus
74 GPa 11 x 106 psi
Shear Strength
440 MPa 63 x 103 psi
Tensile Strength: Ultimate (UTS)
710 MPa 100 x 103 psi
Tensile Strength: Yield (Proof)
480 MPa 69 x 103 psi
Thermal Properties
Latent Heat of Fusion
260 J/g
Maximum Temperature: Mechanical
510 °C 950 °F
Melting Completion (Liquidus)
1460 °C 2660 °F
Melting Onset (Solidus)
1420 °C 2590 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
40 W/m-K 23 BTU/h-ft-°F
Thermal Expansion
13 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
8.1 % IACS
Electrical Conductivity: Equal Weight (Specific)
9.3 % IACS
Otherwise Unclassified Properties
Base Metal Price
4.3 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
1.7 kg CO2/kg material
Embodied Energy
23 MJ/kg 10 x 103 BTU/lb
Embodied Water
69 L/kg 8.2 gal/lb
Common Calculations
PREN (Pitting Resistance)
6.8
Resilience: Ultimate (Unit Rupture Work)
100 MJ/m3
Resilience: Unit (Modulus of Resilience)
600 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
25 points
Strength to Weight: Bending
23 points
Thermal Diffusivity
11 mm2/s
Thermal Shock Resistance
20 points
Alloy Composition
Among alloy steels, the composition of EN 1.7390 steel is notable for containing a comparatively high amount of chromium (Cr). Chromium is used to improve corrosion resistance and most mechanical properties (particularly at higher temperatures).
| Fe | 91.9 to 95.3 | |
| Cr | 4.0 to 6.0 | |
| Mn | 0.3 to 0.8 | |
| Mo | 0.45 to 0.65 | |
| Si | 0 to 0.4 | |
| C | 0 to 0.18 | |
| 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 10269: Steels and nickel alloys for fasteners with specified elevated and/or low temperature properties
Creep-Resistant Steels, Fujio Abe et al. (editors), 2008
Microstructure of Steels and Cast Irons, Madeleine Durand-Charre, 2004
Manufacture and Uses of Alloy Steels, Henry D. Hibbard, 2005
Ferrous Materials: Steel and Cast Iron, Hans Berns and Werner Theisen, 2008
Steels: Processing, Structure, and Performance, 2nd ed., George Krauss, 2015