ASTM A356 Grade 5 vs. ASTM A356 Grade 8
Both ASTM A356 grade 5 and ASTM A356 grade 8 are iron alloys. Both are furnished in the heat treated (HT) condition. They have a very high 98% of their average alloy composition in common.
For each property being compared, the top bar is ASTM A356 grade 5 and the bottom bar is ASTM A356 grade 8.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 170 | |
| 190 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 25 | |
| 21 |
| Fatigue Strength, MPa | 230 | |
| 270 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Reduction in Area, % | 39 | |
| 50 |
| Shear Modulus, GPa | 73 | |
| 73 |
| Tensile Strength: Ultimate (UTS), MPa | 550 | |
| 630 |
| Tensile Strength: Yield (Proof), MPa | 310 | |
| 390 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 260 |
| Maximum Temperature: Mechanical, °C | 420 | |
| 440 |
| Melting Completion (Liquidus), °C | 1470 | |
| 1470 |
| Melting Onset (Solidus), °C | 1420 | |
| 1430 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 49 | |
| 38 |
| Thermal Expansion, µm/m-K | 13 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.2 | |
| 7.5 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.3 | |
| 8.6 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 2.6 | |
| 3.5 |
| Density, g/cm3 | 7.9 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 1.5 | |
| 2.0 |
| Embodied Energy, MJ/kg | 20 | |
| 26 |
| Embodied Water, L/kg | 49 | |
| 55 |
Common Calculations
| PREN (Pitting Resistance) | 2.2 | |
| 4.7 |
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 120 | |
| 110 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 250 | |
| 390 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 20 | |
| 22 |
| Strength to Weight: Bending, points | 19 | |
| 21 |
| Thermal Diffusivity, mm2/s | 13 | |
| 10 |
| Thermal Shock Resistance, points | 16 | |
| 18 |
Alloy Composition
| Carbon (C), % | 0 to 0.25 | |
| 0 to 0.2 |
| Chromium (Cr), % | 0.4 to 0.7 | |
| 1.0 to 1.5 |
| Iron (Fe), % | 97.1 to 99.2 | |
| 95.4 to 97.4 |
| Manganese (Mn), % | 0 to 0.7 | |
| 0.5 to 0.9 |
| Molybdenum (Mo), % | 0.4 to 0.6 | |
| 0.9 to 1.2 |
| Phosphorus (P), % | 0 to 0.035 | |
| 0 to 0.035 |
| Silicon (Si), % | 0 to 0.6 | |
| 0.2 to 0.6 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.030 |
| Vanadium (V), % | 0 | |
| 0.050 to 0.15 |