ASTM A387 Grade 21 Steel vs. Titanium 15-3-3-3
ASTM A387 grade 21 steel belongs to the iron alloys classification, while titanium 15-3-3-3 belongs to the titanium alloys. There are 29 material properties with values for both materials. Properties with values for just one material (3, 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 titanium 15-3-3-3.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 100 |
| Elongation at Break, % | 21 | |
| 5.7 to 8.0 |
| Fatigue Strength, MPa | 160 to 250 | |
| 610 to 710 |
| Poisson's Ratio | 0.29 | |
| 0.33 |
| Shear Modulus, GPa | 74 | |
| 39 |
| Shear Strength, MPa | 310 to 370 | |
| 660 to 810 |
| Tensile Strength: Ultimate (UTS), MPa | 500 to 590 | |
| 1120 to 1390 |
| Tensile Strength: Yield (Proof), MPa | 230 to 350 | |
| 1100 to 1340 |
Thermal Properties
| Latent Heat of Fusion, J/g | 260 | |
| 390 |
| Maximum Temperature: Mechanical, °C | 480 | |
| 430 |
| Melting Completion (Liquidus), °C | 1470 | |
| 1620 |
| Melting Onset (Solidus), °C | 1430 | |
| 1560 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 520 |
| Thermal Conductivity, W/m-K | 41 | |
| 8.1 |
| Thermal Expansion, µm/m-K | 13 | |
| 9.8 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.6 | |
| 1.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.8 | |
| 2.3 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 4.1 | |
| 40 |
| Density, g/cm3 | 7.9 | |
| 4.8 |
| Embodied Carbon, kg CO2/kg material | 1.8 | |
| 59 |
| Embodied Energy, MJ/kg | 23 | |
| 950 |
| Embodied Water, L/kg | 62 | |
| 260 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 84 to 110 | |
| 78 to 89 |
| Stiffness to Weight: Axial, points | 13 | |
| 12 |
| Stiffness to Weight: Bending, points | 24 | |
| 32 |
| Strength to Weight: Axial, points | 18 to 21 | |
| 64 to 80 |
| Strength to Weight: Bending, points | 18 to 20 | |
| 50 to 57 |
| Thermal Diffusivity, mm2/s | 11 | |
| 3.2 |
| Thermal Shock Resistance, points | 14 to 17 | |
| 79 to 98 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 2.5 to 3.5 |
| Carbon (C), % | 0.050 to 0.15 | |
| 0 to 0.050 |
| Chromium (Cr), % | 2.8 to 3.3 | |
| 2.5 to 3.5 |
| Hydrogen (H), % | 0 | |
| 0 to 0.015 |
| Iron (Fe), % | 94.4 to 96 | |
| 0 to 0.25 |
| Manganese (Mn), % | 0.3 to 0.6 | |
| 0 |
| Molybdenum (Mo), % | 0.9 to 1.1 | |
| 0 |
| Nitrogen (N), % | 0 | |
| 0 to 0.050 |
| Oxygen (O), % | 0 | |
| 0 to 0.13 |
| Phosphorus (P), % | 0 to 0.025 | |
| 0 |
| Silicon (Si), % | 0 to 0.5 | |
| 0 |
| Sulfur (S), % | 0 to 0.025 | |
| 0 |
| Tin (Sn), % | 0 | |
| 2.5 to 3.5 |
| Titanium (Ti), % | 0 | |
| 72.6 to 78.5 |
| Vanadium (V), % | 0 | |
| 14 to 16 |
| Residuals, % | 0 | |
| 0 to 0.4 |