ASTM A387 Grade 12 Class 2 Steel
ASTM A387 grade 12 class 2 is ASTM A387 grade 12 steel in the normalized and tempered condition. The graph bars on the material properties cards below compare ASTM A387 grade 12 class 2 to: wrought alloy steels in the same category (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
160
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Elongation at Break
25 %
Fatigue Strength
230 MPa 33 x 103 psi
Poisson's Ratio
0.29
Shear Modulus
73 GPa 11 x 106 psi
Shear Strength
330 MPa 48 x 103 psi
Tensile Strength: Ultimate (UTS)
520 MPa 75 x 103 psi
Tensile Strength: Yield (Proof)
310 MPa 45 x 103 psi
Thermal Properties
Latent Heat of Fusion
250 J/g
Maximum Temperature: Mechanical
430 °C 800 °F
Melting Completion (Liquidus)
1470 °C 2670 °F
Melting Onset (Solidus)
1420 °C 2600 °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
7.2 % IACS
Electrical Conductivity: Equal Weight (Specific)
8.3 % IACS
Otherwise Unclassified Properties
Base Metal Price
2.8 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
1.6 kg CO2/kg material
Embodied Energy
21 MJ/kg 8.9 x 103 BTU/lb
Embodied Water
51 L/kg 6.1 gal/lb
Common Calculations
PREN (Pitting Resistance)
2.7
Resilience: Ultimate (Unit Rupture Work)
110 MJ/m3
Resilience: Unit (Modulus of Resilience)
250 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
18 points
Strength to Weight: Bending
18 points
Thermal Diffusivity
12 mm2/s
Thermal Shock Resistance
15 points
Alloy Composition
| Fe | 97 to 98.2 | |
| Cr | 0.8 to 1.2 | |
| Mn | 0.4 to 0.65 | |
| Mo | 0.45 to 0.6 | |
| Si | 0.15 to 0.4 | |
| C | 0.050 to 0.17 | |
| P | 0 to 0.025 | |
| S | 0 to 0.025 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Further Reading
ASTM A387: Standard Specification for Pressure Vessel Plates, Alloy Steel, Chromium-Molybdenum
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
Steels: Processing, Structure, and Performance, 2nd ed., George Krauss, 2015