EN 1.6958 (26NiCrMo14-6) Nickel-Chromium Steel
EN 1.6958 steel is an alloy steel formulated for primary forming into wrought products. Cited properties are appropriate for the quenched and tempered condition. 1.6958 is the EN numeric designation for this material. 26NiCrMo14-6 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 1.6958 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
340
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Elongation at Break
16 %
Fatigue Strength
700 MPa 100 x 103 psi
Impact Strength: V-Notched Charpy
63 J 46 ft-lb
Poisson's Ratio
0.29
Reduction in Area
56 %
Shear Modulus
73 GPa 11 x 106 psi
Shear Strength
700 MPa 100 x 103 psi
Tensile Strength: Ultimate (UTS)
1140 MPa 170 x 103 psi
Tensile Strength: Yield (Proof)
1070 MPa 160 x 103 psi
Thermal Properties
Latent Heat of Fusion
250 J/g
Maximum Temperature: Mechanical
450 °C 830 °F
Melting Completion (Liquidus)
1460 °C 2660 °F
Melting Onset (Solidus)
1420 °C 2580 °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
11 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
2.0 kg CO2/kg material
Embodied Energy
27 MJ/kg 12 x 103 BTU/lb
Embodied Water
60 L/kg 7.2 gal/lb
Common Calculations
PREN (Pitting Resistance)
2.9
Resilience: Ultimate (Unit Rupture Work)
180 MJ/m3
Resilience: Unit (Modulus of Resilience)
3050 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
40 points
Strength to Weight: Bending
31 points
Thermal Diffusivity
13 mm2/s
Thermal Shock Resistance
39 points
Alloy Composition
Among alloy steels, the composition of EN 1.6958 steel is notable for including aluminum (Al) and vanadium (V). Aluminum is used to control grain size and to deoxidize. Deoxidizing is required to control the effects of some other alloying elements. Vanadium has a strong hardening effect, but this effect is particularly sensitive to the type of tempering.
| Fe | 92.6 to 94.5 | |
| Ni | 3.3 to 3.8 | |
| Cr | 1.2 to 1.7 | |
| Mo | 0.35 to 0.55 | |
| Mn | 0.2 to 0.5 | |
| C | 0.25 to 0.3 | |
| Si | 0.15 to 0.3 | |
| V | 0 to 0.12 | |
| Al | 0.0050 to 0.050 | |
| P | 0 to 0.020 | |
| 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
Manufacture and Uses of Alloy Steels, Henry D. Hibbard, 2005
Ferrous Materials: Steel and Cast Iron, Hans Berns and Werner Theisen, 2008
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015
Steels: Processing, Structure, and Performance, 2nd ed., George Krauss, 2015