ASTM A387 Grade 21 Steel vs. ASTM B522 Class I
ASTM A387 grade 21 steel belongs to the iron alloys classification, while ASTM B522 class I belongs to the otherwise unclassified metals. There are 22 material properties with values for both materials. Properties with values for just one material (11, in this case) are not shown. Please note that the two materials have significantly dissimilar densities. This means that additional care is required when interpreting the data, because some material properties are based on units of mass, while others are based on units of area or volume.
For each property being compared, the top bar is ASTM A387 grade 21 steel and the bottom bar is ASTM B522 class I.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 96 |
| Elongation at Break, % | 21 | |
| 1.1 to 29 |
| Poisson's Ratio | 0.29 | |
| 0.41 |
| Shear Modulus, GPa | 74 | |
| 34 |
| Shear Strength, MPa | 310 to 370 | |
| 180 to 280 |
| Tensile Strength: Ultimate (UTS), MPa | 500 to 590 | |
| 280 to 490 |
| Tensile Strength: Yield (Proof), MPa | 230 to 350 | |
| 120 to 210 |
Thermal Properties
| Latent Heat of Fusion, J/g | 260 | |
| 77 |
| Melting Completion (Liquidus), °C | 1470 | |
| 1030 |
| Melting Onset (Solidus), °C | 1430 | |
| 1030 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 160 |
| Thermal Expansion, µm/m-K | 13 | |
| 15 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.6 | |
| 11 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.8 | |
| 5.8 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.9 | |
| 17 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 84 to 110 | |
| 4.5 to 64 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 140 to 320 | |
| 75 to 230 |
| Stiffness to Weight: Axial, points | 13 | |
| 3.1 |
| Stiffness to Weight: Bending, points | 24 | |
| 8.9 |
| Strength to Weight: Axial, points | 18 to 21 | |
| 4.4 to 7.8 |
| Strength to Weight: Bending, points | 18 to 20 | |
| 5.5 to 8.0 |
| Thermal Shock Resistance, points | 14 to 17 | |
| 13 to 24 |
Alloy Composition
| Carbon (C), % | 0.050 to 0.15 | |
| 0 |
| Chromium (Cr), % | 2.8 to 3.3 | |
| 0 |
| Gold (Au), % | 0 | |
| 68 to 70 |
| Iron (Fe), % | 94.4 to 96 | |
| 0 |
| Manganese (Mn), % | 0.3 to 0.6 | |
| 0 |
| Molybdenum (Mo), % | 0.9 to 1.1 | |
| 0 |
| Phosphorus (P), % | 0 to 0.025 | |
| 0 |
| Platinum (Pt), % | 0 | |
| 5.0 to 7.0 |
| Silicon (Si), % | 0 to 0.5 | |
| 0 |
| Silver (Ag), % | 0 | |
| 23.5 to 26.5 |
| Sulfur (S), % | 0 to 0.025 | |
| 0 |
| Residuals, % | 0 | |
| 0 to 0.35 |