ASTM A387 Grade 91 Class 2 vs. EV31A Magnesium
ASTM A387 grade 91 class 2 belongs to the iron alloys classification, while EV31A magnesium belongs to the magnesium alloys. There are 25 material properties with values for both materials. Properties with values for just one material (9, in this case) are not shown. Please note that the two materials have significantly dissimilar densities. This means that additional care is required when interpreting the data, because some material properties are based on units of mass, while others are based on units of area or volume.
For each property being compared, the top bar is ASTM A387 grade 91 class 2 and the bottom bar is EV31A magnesium.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 200 | |
| 70 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 44 |
| Elongation at Break, % | 20 | |
| 3.5 |
| Fatigue Strength, MPa | 330 | |
| 120 |
| Poisson's Ratio | 0.28 | |
| 0.27 |
| Shear Modulus, GPa | 75 | |
| 17 |
| Shear Strength, MPa | 420 | |
| 170 |
| Tensile Strength: Ultimate (UTS), MPa | 670 | |
| 260 |
| Tensile Strength: Yield (Proof), MPa | 470 | |
| 170 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 600 | |
| 200 |
| Melting Onset (Solidus), °C | 1420 | |
| 590 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 1000 |
| Thermal Conductivity, W/m-K | 26 | |
| 86 |
| Thermal Expansion, µm/m-K | 13 | |
| 27 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 8.9 | |
| 18 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 10 | |
| 90 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.8 | |
| 1.8 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 120 | |
| 8.1 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 580 | |
| 330 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 25 | |
| 65 |
| Strength to Weight: Axial, points | 24 | |
| 40 |
| Strength to Weight: Bending, points | 22 | |
| 50 |
| Thermal Diffusivity, mm2/s | 6.9 | |
| 47 |
| Thermal Shock Resistance, points | 19 | |
| 16 |