EN 1.8522 (33CrMoV12-9) High-Temperature Bearing Steel
EN 1.8522 steel is an alloy steel formulated for primary forming into wrought products. 1.8522 is the EN numeric designation for this material. 33CrMoV12-9 is the EN chemical designation.
It has a fairly low thermal conductivity among EN wrought alloy steels. In addition, it has a very high embodied energy and a fairly high base cost.
The properties of EN 1.8522 steel include two common variations. This page shows summary ranges across both of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare EN 1.8522 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
220 to 380
Elastic (Young's, Tensile) Modulus
190 GPa 28 x 106 psi
Poisson's Ratio
0.29
Shear Modulus
74 GPa 11 x 106 psi
Tensile Strength: Ultimate (UTS)
730 to 1250 MPa 110 to 180 x 103 psi
Thermal Properties
Latent Heat of Fusion
260 J/g
Maximum Temperature: Mechanical
470 °C 890 °F
Melting Completion (Liquidus)
1460 °C 2670 °F
Melting Onset (Solidus)
1420 °C 2590 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
39 W/m-K 22 BTU/h-ft-°F
Thermal Expansion
13 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
7.8 % IACS
Electrical Conductivity: Equal Weight (Specific)
8.9 % IACS
Otherwise Unclassified Properties
Base Metal Price
4.2 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
2.2 kg CO2/kg material
Embodied Energy
31 MJ/kg 13 x 103 BTU/lb
Embodied Water
63 L/kg 7.5 gal/lb
Common Calculations
PREN (Pitting Resistance)
6.2
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
26 to 44 points
Strength to Weight: Bending
23 to 33 points
Thermal Diffusivity
11 mm2/s
Thermal Shock Resistance
21 to 36 points
Alloy Composition
Among alloy steels, the composition of EN 1.8522 steel is notable for containing a comparatively high amount of chromium (Cr) and including vanadium (V). Chromium is used to improve corrosion resistance and most mechanical properties (particularly at higher temperatures). Vanadium has a strong hardening effect, but this effect is particularly sensitive to the type of tempering.
| Fe | 93.7 to 96 | |
| Cr | 2.8 to 3.3 | |
| Mo | 0.7 to 1.2 | |
| Mn | 0.4 to 0.7 | |
| C | 0.29 to 0.36 | |
| Si | 0 to 0.4 | |
| V | 0.15 to 0.25 | |
| Ni | 0 to 0.3 | |
| Cu | 0 to 0.1 | |
| S | 0 to 0.035 | |
| P | 0 to 0.025 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ISO 683-5: Heat treatable steels, alloy steels and free-cutting steels - Part 5: Nitriding steels
ISO 683-17: Heat-treated steels, alloy steels and free-cutting steels - Part 17: Ball and roller bearing steels
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