ASTM A231 Spring Steel vs. Grade 9 Titanium
ASTM A231 spring steel belongs to the iron alloys classification, while grade 9 titanium belongs to the titanium alloys. There are 30 material properties with values for both materials. Properties with values for just one material (2, in this case) are not shown.
For each property being compared, the top bar is ASTM A231 spring steel and the bottom bar is grade 9 titanium.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 110 |
| Elongation at Break, % | 14 | |
| 11 to 17 |
| Fatigue Strength, MPa | 1000 | |
| 330 to 480 |
| Poisson's Ratio | 0.29 | |
| 0.32 |
| Reduction in Area, % | 46 | |
| 28 |
| Shear Modulus, GPa | 73 | |
| 40 |
| Shear Strength, MPa | 1080 | |
| 430 to 580 |
| Tensile Strength: Ultimate (UTS), MPa | 1790 | |
| 700 to 960 |
| Tensile Strength: Yield (Proof), MPa | 1570 | |
| 540 to 830 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 410 |
| Maximum Temperature: Mechanical, °C | 420 | |
| 330 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1640 |
| Melting Onset (Solidus), °C | 1410 | |
| 1590 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 550 |
| Thermal Conductivity, W/m-K | 52 | |
| 8.1 |
| Thermal Expansion, µm/m-K | 13 | |
| 9.1 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.3 | |
| 1.4 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.4 | |
| 2.7 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 2.3 | |
| 37 |
| Density, g/cm3 | 7.8 | |
| 4.5 |
| Embodied Carbon, kg CO2/kg material | 2.0 | |
| 36 |
| Embodied Energy, MJ/kg | 28 | |
| 580 |
| Embodied Water, L/kg | 51 | |
| 150 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 230 | |
| 89 to 110 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 35 |
| Strength to Weight: Axial, points | 64 | |
| 43 to 60 |
| Strength to Weight: Bending, points | 42 | |
| 39 to 48 |
| Thermal Diffusivity, mm2/s | 14 | |
| 3.3 |
| Thermal Shock Resistance, points | 53 | |
| 52 to 71 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 2.5 to 3.5 |
| Carbon (C), % | 0.48 to 0.53 | |
| 0 to 0.080 |
| Chromium (Cr), % | 0.8 to 1.1 | |
| 0 |
| Hydrogen (H), % | 0 | |
| 0 to 0.015 |
| Iron (Fe), % | 96.7 to 97.7 | |
| 0 to 0.25 |
| Manganese (Mn), % | 0.7 to 0.9 | |
| 0 |
| Nitrogen (N), % | 0 | |
| 0 to 0.030 |
| Oxygen (O), % | 0 | |
| 0 to 0.15 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0 |
| Sulfur (S), % | 0 to 0.040 | |
| 0 |
| Titanium (Ti), % | 0 | |
| 92.6 to 95.5 |
| Vanadium (V), % | 0.15 to 0.3 | |
| 2.0 to 3.0 |
| Residuals, % | 0 | |
| 0 to 0.4 |