ASTM A387 Grade 91 Class 2 vs. AISI 403 Stainless Steel
Both ASTM A387 grade 91 class 2 and AISI 403 stainless steel are iron alloys. They have a very high 96% of their average alloy composition in common. There are 32 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 91 class 2 and the bottom bar is AISI 403 stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 200 | |
| 190 to 240 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 20 | |
| 16 to 25 |
| Fatigue Strength, MPa | 330 | |
| 200 to 340 |
| Poisson's Ratio | 0.28 | |
| 0.28 |
| Shear Modulus, GPa | 75 | |
| 76 |
| Shear Strength, MPa | 420 | |
| 340 to 480 |
| Tensile Strength: Ultimate (UTS), MPa | 670 | |
| 530 to 780 |
| Tensile Strength: Yield (Proof), MPa | 470 | |
| 280 to 570 |
Thermal Properties
| Latent Heat of Fusion, J/g | 270 | |
| 270 |
| Maximum Temperature: Mechanical, °C | 600 | |
| 740 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1450 |
| Melting Onset (Solidus), °C | 1420 | |
| 1400 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 480 |
| Thermal Conductivity, W/m-K | 26 | |
| 28 |
| Thermal Expansion, µm/m-K | 13 | |
| 9.9 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 8.9 | |
| 2.9 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 10 | |
| 3.3 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 7.0 | |
| 6.5 |
| Density, g/cm3 | 7.8 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 2.6 | |
| 1.9 |
| Embodied Energy, MJ/kg | 37 | |
| 27 |
| Embodied Water, L/kg | 88 | |
| 99 |
Common Calculations
| PREN (Pitting Resistance) | 13 | |
| 12 |
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 120 | |
| 110 to 120 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 580 | |
| 210 to 840 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 25 | |
| 25 |
| Strength to Weight: Axial, points | 24 | |
| 19 to 28 |
| Strength to Weight: Bending, points | 22 | |
| 19 to 24 |
| Thermal Diffusivity, mm2/s | 6.9 | |
| 7.6 |
| Thermal Shock Resistance, points | 19 | |
| 20 to 29 |
Alloy Composition
| Aluminum (Al), % | 0 to 0.020 | |
| 0 |
| Carbon (C), % | 0.080 to 0.12 | |
| 0 to 0.15 |
| Chromium (Cr), % | 8.0 to 9.5 | |
| 11.5 to 13 |
| Iron (Fe), % | 87.3 to 90.3 | |
| 84.7 to 88.5 |
| Manganese (Mn), % | 0.3 to 0.6 | |
| 0 to 1.0 |
| Molybdenum (Mo), % | 0.85 to 1.1 | |
| 0 |
| Nickel (Ni), % | 0 to 0.4 | |
| 0 to 0.6 |
| Niobium (Nb), % | 0.060 to 0.1 | |
| 0 |
| Nitrogen (N), % | 0.030 to 0.070 | |
| 0 |
| Phosphorus (P), % | 0 to 0.020 | |
| 0 to 0.040 |
| Silicon (Si), % | 0.2 to 0.5 | |
| 0 to 0.5 |
| Sulfur (S), % | 0 to 0.010 | |
| 0 to 0.030 |
| Titanium (Ti), % | 0 to 0.010 | |
| 0 |
| Vanadium (V), % | 0.18 to 0.25 | |
| 0 |
| Zirconium (Zr), % | 0 to 0.010 | |
| 0 |