EN 1.6957 (27NiCrMoV15-6) Nickel-Chromium Steel
EN 1.6957 steel is an alloy steel formulated for primary forming into wrought products. Cited properties are appropriate for the quenched and tempered condition. 1.6957 is the EN numeric designation for this material. 27NiCrMoV15-6 is the EN chemical designation.
It has a moderately high density among EN wrought alloy steels. In addition, it has a very high base cost and a very high electrical conductivity.
The graph bars on the material properties cards below compare EN 1.6957 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
280
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Elongation at Break
18 %
Fatigue Strength
530 MPa 77 x 103 psi
Impact Strength: V-Notched Charpy
71 J 52 ft-lb
Poisson's Ratio
0.29
Reduction in Area
46 %
Shear Modulus
73 GPa 11 x 106 psi
Shear Strength
570 MPa 83 x 103 psi
Tensile Strength: Ultimate (UTS)
930 MPa 130 x 103 psi
Tensile Strength: Yield (Proof)
780 MPa 110 x 103 psi
Thermal Properties
Latent Heat of Fusion
250 J/g
Maximum Temperature: Mechanical
450 °C 840 °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
47 W/m-K 27 BTU/h-ft-°F
Thermal Expansion
13 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
7.9 % IACS
Electrical Conductivity: Equal Weight (Specific)
9.1 % IACS
Otherwise Unclassified Properties
Base Metal Price
5.0 % relative
Density
7.9 g/cm3 490 lb/ft3
Embodied Carbon
2.1 kg CO2/kg material
Embodied Energy
29 MJ/kg 12 x 103 BTU/lb
Embodied Water
60 L/kg 7.2 gal/lb
Common Calculations
PREN (Pitting Resistance)
2.7
Resilience: Ultimate (Unit Rupture Work)
160 MJ/m3
Resilience: Unit (Modulus of Resilience)
1630 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
33 points
Strength to Weight: Bending
27 points
Thermal Diffusivity
13 mm2/s
Thermal Shock Resistance
27 points
Alloy Composition
Among alloy steels, the composition of EN 1.6957 steel is notable for including vanadium (V) and nickel (Ni). Vanadium has a strong hardening effect, but this effect is particularly sensitive to the type of tempering. Nickel is used to improve mechanical properties, and to make the alloy easier to heat treat.
| Fe | 92.7 to 94.7 | |
| Ni | 3.4 to 4.0 | |
| Cr | 1.2 to 1.8 | |
| Mo | 0.25 to 0.45 | |
| Mn | 0.15 to 0.4 | |
| C | 0.22 to 0.32 | |
| V | 0.050 to 0.15 | |
| Si | 0 to 0.15 | |
| P | 0 to 0.010 | |
| S | 0 to 0.0070 |
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
Microstructure of Steels and Cast Irons, Madeleine Durand-Charre, 2004
ASM Specialty Handbook: Carbon and Alloy Steels, J. R. Davis (editor), 1996
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