ASTM A387 Grade 21 Steel vs. ASTM B817 Type I
ASTM A387 grade 21 steel belongs to the iron alloys classification, while ASTM B817 type I belongs to the titanium alloys. There are 29 material properties with values for both materials. Properties with values for just one material (4, in this case) are not shown.
For each property being compared, the top bar is ASTM A387 grade 21 steel and the bottom bar is ASTM B817 type I.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 100 |
| Elongation at Break, % | 21 | |
| 4.0 to 13 |
| Fatigue Strength, MPa | 160 to 250 | |
| 360 to 520 |
| Poisson's Ratio | 0.29 | |
| 0.32 |
| Shear Modulus, GPa | 74 | |
| 40 |
| Tensile Strength: Ultimate (UTS), MPa | 500 to 590 | |
| 770 to 960 |
| Tensile Strength: Yield (Proof), MPa | 230 to 350 | |
| 700 to 860 |
Thermal Properties
| Latent Heat of Fusion, J/g | 260 | |
| 410 |
| Maximum Temperature: Mechanical, °C | 480 | |
| 340 |
| Melting Completion (Liquidus), °C | 1470 | |
| 1600 |
| Melting Onset (Solidus), °C | 1430 | |
| 1550 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 560 |
| Thermal Conductivity, W/m-K | 41 | |
| 7.1 |
| Thermal Expansion, µm/m-K | 13 | |
| 9.6 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.6 | |
| 1.0 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.8 | |
| 2.0 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 4.1 | |
| 36 |
| Density, g/cm3 | 7.9 | |
| 4.4 |
| Embodied Carbon, kg CO2/kg material | 1.8 | |
| 38 |
| Embodied Energy, MJ/kg | 23 | |
| 610 |
| Embodied Water, L/kg | 62 | |
| 200 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 84 to 110 | |
| 30 to 120 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 140 to 320 | |
| 2310 to 3540 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 35 |
| Strength to Weight: Axial, points | 18 to 21 | |
| 48 to 60 |
| Strength to Weight: Bending, points | 18 to 20 | |
| 42 to 49 |
| Thermal Diffusivity, mm2/s | 11 | |
| 2.9 |
| Thermal Shock Resistance, points | 14 to 17 | |
| 54 to 68 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 5.5 to 6.8 |
| Carbon (C), % | 0.050 to 0.15 | |
| 0 to 0.1 |
| Chlorine (Cl), % | 0 | |
| 0 to 0.2 |
| Chromium (Cr), % | 2.8 to 3.3 | |
| 0 |
| Hydrogen (H), % | 0 | |
| 0 to 0.015 |
| Iron (Fe), % | 94.4 to 96 | |
| 0 to 0.4 |
| Manganese (Mn), % | 0.3 to 0.6 | |
| 0 |
| Molybdenum (Mo), % | 0.9 to 1.1 | |
| 0 |
| Nitrogen (N), % | 0 | |
| 0 to 0.040 |
| Oxygen (O), % | 0 | |
| 0 to 0.3 |
| Phosphorus (P), % | 0 to 0.025 | |
| 0 |
| Silicon (Si), % | 0 to 0.5 | |
| 0 to 0.1 |
| Sodium (Na), % | 0 | |
| 0 to 0.2 |
| Sulfur (S), % | 0 to 0.025 | |
| 0 |
| Titanium (Ti), % | 0 | |
| 87 to 91 |
| Vanadium (V), % | 0 | |
| 3.5 to 4.5 |
| Residuals, % | 0 | |
| 0 to 0.4 |