Quenched and Tempered (+QT) 1.7218 Steel
EN 1.7218 +QT steel is EN 1.7218 steel in the quenched and tempered condition. The graph bars on the material properties cards below compare EN 1.7218 +QT 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
230
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Elongation at Break
16 %
Fatigue Strength
350 MPa 50 x 103 psi
Impact Strength: V-Notched Charpy
49 J 36 ft-lb
Poisson's Ratio
0.29
Reduction in Area
68 %
Rockwell C Hardness
48
Shear Modulus
73 GPa 11 x 106 psi
Shear Strength
470 MPa 68 x 103 psi
Tensile Strength: Ultimate (UTS)
760 MPa 110 x 103 psi
Tensile Strength: Yield (Proof)
530 MPa 77 x 103 psi
Thermal Properties
Latent Heat of Fusion
250 J/g
Maximum Temperature: Mechanical
420 °C 800 °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
44 W/m-K 26 BTU/h-ft-°F
Thermal Expansion
13 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
7.4 % IACS
Electrical Conductivity: Equal Weight (Specific)
8.5 % IACS
Otherwise Unclassified Properties
Base Metal Price
2.6 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
1.5 kg CO2/kg material
Embodied Energy
20 MJ/kg 8.6 x 103 BTU/lb
Embodied Water
52 L/kg 6.2 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
110 MJ/m3
Resilience: Unit (Modulus of Resilience)
740 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
27 points
Strength to Weight: Bending
24 points
Thermal Diffusivity
12 mm2/s
Thermal Shock Resistance
22 points
Alloy Composition
| Fe | 96.2 to 98.1 | |
| Cr | 0.9 to 1.2 | |
| Mn | 0.6 to 0.9 | |
| C | 0.22 to 0.29 | |
| Mo | 0.15 to 0.3 | |
| Si | 0 to 0.4 | |
| Ni | 0 to 0.3 | |
| Cu | 0 to 0.3 | |
| Al | 0 to 0.040 | |
| P | 0 to 0.035 | |
| S | 0 to 0.035 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
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
EN 10297-1: Seamless circular steel tubes for mechanical and general engineering purposes - Technical delivery conditions - Part 1: Non-alloy and alloy steel tubes
EN 10250-3: Open die steel forgings for general engineering purposes - Part 3: Alloy special steels
EN 10269: Steels and nickel alloys for fasteners with specified elevated and/or low temperature properties
Creep-Resistant Steels, Fujio Abe et al. (editors), 2008
Pressure Vessels: External Pressure Technology, 2nd ed., Carl T. F. Ross, 2011
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