SAE-AISI D4 Steel vs. Grade 21 Titanium
SAE-AISI D4 steel belongs to the iron alloys classification, while grade 21 titanium belongs to the titanium alloys. There are 26 material properties with values for both materials. Properties with values for just one material (6, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI D4 steel and the bottom bar is grade 21 titanium.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 140 |
| Elongation at Break, % | 8.4 to 15 | |
| 9.0 to 17 |
| Fatigue Strength, MPa | 310 to 920 | |
| 550 to 660 |
| Poisson's Ratio | 0.28 | |
| 0.32 |
| Shear Modulus, GPa | 74 | |
| 51 |
| Shear Strength, MPa | 460 to 1210 | |
| 550 to 790 |
| Tensile Strength: Ultimate (UTS), MPa | 760 to 2060 | |
| 890 to 1340 |
| Tensile Strength: Yield (Proof), MPa | 470 to 1540 | |
| 870 to 1170 |
Thermal Properties
| Latent Heat of Fusion, J/g | 270 | |
| 410 |
| Melting Completion (Liquidus), °C | 1430 | |
| 1740 |
| Melting Onset (Solidus), °C | 1380 | |
| 1690 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 500 |
| Thermal Conductivity, W/m-K | 31 | |
| 7.5 |
| Thermal Expansion, µm/m-K | 12 | |
| 7.1 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 8.0 | |
| 60 |
| Density, g/cm3 | 7.7 | |
| 5.4 |
| Embodied Carbon, kg CO2/kg material | 3.3 | |
| 32 |
| Embodied Energy, MJ/kg | 49 | |
| 490 |
| Embodied Water, L/kg | 100 | |
| 180 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 100 to 160 | |
| 110 to 180 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 25 | |
| 32 |
| Strength to Weight: Axial, points | 27 to 75 | |
| 46 to 69 |
| Strength to Weight: Bending, points | 24 to 47 | |
| 38 to 50 |
| Thermal Diffusivity, mm2/s | 8.3 | |
| 2.8 |
| Thermal Shock Resistance, points | 23 to 63 | |
| 66 to 100 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 2.5 to 3.5 |
| Carbon (C), % | 2.1 to 2.4 | |
| 0 to 0.050 |
| Chromium (Cr), % | 11 to 13 | |
| 0 |
| Copper (Cu), % | 0 to 0.25 | |
| 0 |
| Hydrogen (H), % | 0 | |
| 0 to 0.015 |
| Iron (Fe), % | 80.6 to 86.3 | |
| 0 to 0.4 |
| Manganese (Mn), % | 0 to 0.6 | |
| 0 |
| Molybdenum (Mo), % | 0.7 to 1.2 | |
| 14 to 16 |
| Nickel (Ni), % | 0 to 0.3 | |
| 0 |
| Niobium (Nb), % | 0 | |
| 2.2 to 3.2 |
| Nitrogen (N), % | 0 | |
| 0 to 0.030 |
| Oxygen (O), % | 0 | |
| 0 to 0.17 |
| Phosphorus (P), % | 0 to 0.030 | |
| 0 |
| Silicon (Si), % | 0 to 0.6 | |
| 0.15 to 0.25 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 |
| Titanium (Ti), % | 0 | |
| 76 to 81.2 |
| Vanadium (V), % | 0 to 1.0 | |
| 0 |
| Residuals, % | 0 | |
| 0 to 0.4 |