Type 4 Niobium vs. S81921 Stainless Steel
Type 4 niobium belongs to the otherwise unclassified metals classification, while S81921 stainless steel belongs to the iron alloys. There are 21 material properties with values for both materials. Properties with values for just one material (13, in this case) are not shown.
For each property being compared, the top bar is Type 4 niobium and the bottom bar is S81921 stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 120 | |
| 260 |
| Elastic (Young's, Tensile) Modulus, GPa | 110 | |
| 200 |
| Elongation at Break, % | 23 | |
| 29 |
| Poisson's Ratio | 0.4 | |
| 0.28 |
| Shear Modulus, GPa | 38 | |
| 79 |
| Tensile Strength: Ultimate (UTS), MPa | 220 | |
| 710 |
| Tensile Strength: Yield (Proof), MPa | 140 | |
| 500 |
Thermal Properties
| Latent Heat of Fusion, J/g | 310 | |
| 290 |
| Specific Heat Capacity, J/kg-K | 270 | |
| 480 |
| Thermal Conductivity, W/m-K | 42 | |
| 15 |
| Thermal Expansion, µm/m-K | 7.3 | |
| 13 |
Otherwise Unclassified Properties
| Density, g/cm3 | 8.6 | |
| 7.7 |
| Embodied Water, L/kg | 160 | |
| 150 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 44 | |
| 180 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 93 | |
| 630 |
| Stiffness to Weight: Axial, points | 6.8 | |
| 14 |
| Stiffness to Weight: Bending, points | 18 | |
| 25 |
| Strength to Weight: Axial, points | 7.2 | |
| 25 |
| Strength to Weight: Bending, points | 9.5 | |
| 23 |
| Thermal Diffusivity, mm2/s | 18 | |
| 4.0 |
| Thermal Shock Resistance, points | 21 | |
| 20 |
Alloy Composition
| Carbon (C), % | 0 to 0.010 | |
| 0 to 0.030 |
| Chromium (Cr), % | 0 | |
| 19 to 22 |
| Hafnium (Hf), % | 0 to 0.020 | |
| 0 |
| Hydrogen (H), % | 0 to 0.0015 | |
| 0 |
| Iron (Fe), % | 0 to 0.010 | |
| 66.7 to 75.9 |
| Manganese (Mn), % | 0 | |
| 2.0 to 4.0 |
| Molybdenum (Mo), % | 0 to 0.050 | |
| 1.0 to 2.0 |
| Nickel (Ni), % | 0 to 0.0050 | |
| 2.0 to 4.0 |
| Niobium (Nb), % | 98.1 to 99.2 | |
| 0 |
| Nitrogen (N), % | 0 to 0.010 | |
| 0.14 to 0.2 |
| Oxygen (O), % | 0 to 0.025 | |
| 0 |
| Phosphorus (P), % | 0 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 0.0050 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 | |
| 0 to 0.030 |
| Tantalum (Ta), % | 0 to 0.5 | |
| 0 |
| Titanium (Ti), % | 0 to 0.020 | |
| 0 |
| Tungsten (W), % | 0 to 0.050 | |
| 0 |
| Zirconium (Zr), % | 0.8 to 1.2 | |
| 0 |