EN 1.1244 (70Mn4) Induction-Hardening Bearing Steel
EN 1.1244 steel is a carbon (non-alloy) steel formulated for primary forming into wrought products. 1.1244 is the EN numeric designation for this material. 70Mn4 is the EN chemical designation. It can have a fairly high tensile strength among the wrought carbon or non-alloy steels in the database.
The properties of EN 1.1244 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 1.1244 steel to: wrought carbon or non-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 to 220
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Poisson's Ratio
0.29
Shear Modulus
72 GPa 10 x 106 psi
Tensile Strength: Ultimate (UTS)
730 to 770 MPa 110 x 103 psi
Thermal Properties
Latent Heat of Fusion
250 J/g
Maximum Temperature: Mechanical
400 °C 750 °F
Melting Completion (Liquidus)
1450 °C 2650 °F
Melting Onset (Solidus)
1410 °C 2570 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
51 W/m-K 29 BTU/h-ft-°F
Thermal Expansion
12 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
7.1 % IACS
Electrical Conductivity: Equal Weight (Specific)
8.2 % IACS
Otherwise Unclassified Properties
Base Metal Price
1.9 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
1.4 kg CO2/kg material
Embodied Energy
19 MJ/kg 8.1 x 103 BTU/lb
Embodied Water
47 L/kg 5.6 gal/lb
Common Calculations
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
26 to 28 points
Strength to Weight: Bending
23 to 24 points
Thermal Diffusivity
14 mm2/s
Thermal Shock Resistance
23 to 25 points
Alloy Composition
| Fe | 98.1 to 99.2 | |
| Mn | 0.8 to 1.1 | |
| C | 0.65 to 0.75 | |
| Si | 0 to 0.4 | |
| Cu | 0 to 0.3 | |
| Al | 0 to 0.050 | |
| S | 0 to 0.030 | |
| P | 0 to 0.025 | |
| O | 0 to 0.0020 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ISO 683-17: Heat-treated steels, alloy steels and free-cutting steels - Part 17: Ball and roller bearing steels
Carbon Steel Handbook, D. Gandy, 2007
Ferrous Materials: Steel and Cast Iron, Hans Berns and Werner Theisen, 2008
Steels: Processing, Structure, and Performance, 2nd ed., George Krauss, 2015