ASTM A387 Grade 12 Steel vs. ASTM A372 Grade K Steel
Both ASTM A387 grade 12 steel and ASTM A372 grade K steel are iron alloys. They have a very high 97% of their average alloy composition in common.
For each property being compared, the top bar is ASTM A387 grade 12 steel and the bottom bar is ASTM A372 grade K steel.
Metric UnitsUS Customary Units
Mechanical Properties
Brinell Hardness | 140 to 160 | |
230 |
Elastic (Young's, Tensile) Modulus, GPa | 190 | |
190 |
Elongation at Break, % | 25 | |
23 |
Fatigue Strength, MPa | 190 to 230 | |
440 |
Poisson's Ratio | 0.29 | |
0.29 |
Shear Modulus, GPa | 73 | |
73 |
Shear Strength, MPa | 300 to 330 | |
490 |
Tensile Strength: Ultimate (UTS), MPa | 470 to 520 | |
780 |
Tensile Strength: Yield (Proof), MPa | 260 to 310 | |
620 |
Thermal Properties
Latent Heat of Fusion, J/g | 250 | |
250 |
Maximum Temperature: Mechanical, °C | 430 | |
440 |
Melting Completion (Liquidus), °C | 1470 | |
1460 |
Melting Onset (Solidus), °C | 1420 | |
1420 |
Specific Heat Capacity, J/kg-K | 470 | |
470 |
Thermal Conductivity, W/m-K | 44 | |
48 |
Thermal Expansion, µm/m-K | 13 | |
13 |
Electrical Properties
Electrical Conductivity: Equal Volume, % IACS | 7.2 | |
7.8 |
Electrical Conductivity: Equal Weight (Specific), % IACS | 8.3 | |
8.9 |
Otherwise Unclassified Properties
Base Metal Price, % relative | 2.8 | |
4.4 |
Density, g/cm3 | 7.8 | |
7.9 |
Embodied Carbon, kg CO2/kg material | 1.6 | |
1.8 |
Embodied Energy, MJ/kg | 21 | |
24 |
Embodied Water, L/kg | 51 | |
57 |
Common Calculations
PREN (Pitting Resistance) | 2.7 | |
2.7 |
Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 98 to 110 | |
160 |
Resilience: Unit (Modulus of Resilience), kJ/m3 | 180 to 250 | |
1010 |
Stiffness to Weight: Axial, points | 13 | |
13 |
Stiffness to Weight: Bending, points | 24 | |
24 |
Strength to Weight: Axial, points | 16 to 18 | |
27 |
Strength to Weight: Bending, points | 17 to 18 | |
24 |
Thermal Diffusivity, mm2/s | 12 | |
13 |
Thermal Shock Resistance, points | 14 to 15 | |
23 |
Alloy Composition
Carbon (C), % | 0.050 to 0.17 | |
0 to 0.18 |
Chromium (Cr), % | 0.8 to 1.2 | |
1.0 to 1.8 |
Iron (Fe), % | 97 to 98.2 | |
93.4 to 96.6 |
Manganese (Mn), % | 0.4 to 0.65 | |
0.1 to 0.4 |
Molybdenum (Mo), % | 0.45 to 0.6 | |
0.2 to 0.6 |
Nickel (Ni), % | 0 | |
2.0 to 3.3 |
Phosphorus (P), % | 0 to 0.025 | |
0 to 0.015 |
Silicon (Si), % | 0.15 to 0.4 | |
0.15 to 0.35 |
Sulfur (S), % | 0 to 0.025 | |
0 to 0.010 |