EN 1.8201 (7CrWVMoNb9-6) Chromium-Tungsten Steel
EN 1.8201 steel is an alloy steel formulated for primary forming into wrought products. Cited properties are appropriate for the normalized and tempered condition. 1.8201 is the EN numeric designation for this material. 7CrWVMoNb9-6 is the EN chemical designation.
It has a very high density among EN wrought alloy steels. In addition, it has a very high melting temperature and a very high embodied energy.
The graph bars on the material properties cards below compare EN 1.8201 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
190
Elastic (Young's, Tensile) Modulus
190 GPa 28 x 106 psi
Elongation at Break
20 %
Fatigue Strength
310 MPa 45 x 103 psi
Impact Strength: V-Notched Charpy
38 J 28 ft-lb
Poisson's Ratio
0.29
Shear Modulus
74 GPa 11 x 106 psi
Shear Strength
390 MPa 57 x 103 psi
Tensile Strength: Ultimate (UTS)
630 MPa 91 x 103 psi
Tensile Strength: Yield (Proof)
450 MPa 65 x 103 psi
Thermal Properties
Latent Heat of Fusion
250 J/g
Maximum Temperature: Mechanical
450 °C 840 °F
Melting Completion (Liquidus)
1500 °C 2730 °F
Melting Onset (Solidus)
1450 °C 2650 °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
7.8 % IACS
Electrical Conductivity: Equal Weight (Specific)
8.8 % IACS
Otherwise Unclassified Properties
Base Metal Price
7.0 % relative
Density
8.0 g/cm3 500 lb/ft3
Embodied Carbon
2.5 kg CO2/kg material
Embodied Energy
36 MJ/kg 16 x 103 BTU/lb
Embodied Water
59 L/kg 7.0 gal/lb
Common Calculations
PREN (Pitting Resistance)
5.7
Resilience: Ultimate (Unit Rupture Work)
110 MJ/m3
Resilience: Unit (Modulus of Resilience)
530 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
22 points
Strength to Weight: Bending
20 points
Thermal Diffusivity
11 mm2/s
Thermal Shock Resistance
18 points
Alloy Composition
Among alloy steels, the composition of EN 1.8201 steel is notable for including tungsten (W) and boron (B). Tungsten interacts with other alloying elements to a greater extent than usual, which makes it hard to broadly characterize its effects. Boron is used to improve hardenability. It has a substantial effect when added in even tiny amounts.
| Fe | 93.6 to 96.2 | |
| Cr | 1.9 to 2.6 | |
| W | 1.5 to 1.8 | |
| Mn | 0.1 to 0.6 | |
| Si | 0 to 0.5 | |
| V | 0.2 to 0.3 | |
| Mo | 0.050 to 0.3 | |
| C | 0.040 to 0.1 | |
| Nb | 0.020 to 0.080 | |
| Ti | 0.0050 to 0.060 | |
| P | 0 to 0.030 | |
| Al | 0 to 0.030 | |
| N | 0 to 0.015 | |
| S | 0 to 0.010 | |
| B | 0.0010 to 0.0060 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
EN 10216-2: Seamless steel tubes for pressure purposes - Technical delivery conditions - Part 2: Non-alloy and alloy steel tubes with specified elevated temperature properties
Microstructure of Steels and Cast Irons, Madeleine Durand-Charre, 2004
Pressure Vessels: External Pressure Technology, 2nd ed., Carl T. F. Ross, 2011
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