AISI 304 Stainless Steel vs. AZ91D Magnesium
AISI 304 stainless steel belongs to the iron alloys classification, while AZ91D magnesium belongs to the magnesium alloys. There are 31 material properties with values for both materials. Properties with values for just one material (6, 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 AISI 304 stainless steel and the bottom bar is AZ91D magnesium.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 170 to 360 | |
| 60 to 80 |
| Elastic (Young's, Tensile) Modulus, GPa | 200 | |
| 46 |
| Elongation at Break, % | 8.0 to 43 | |
| 2.3 to 4.5 |
| Fatigue Strength, MPa | 210 to 440 | |
| 74 to 85 |
| Poisson's Ratio | 0.28 | |
| 0.29 |
| Shear Modulus, GPa | 77 | |
| 18 |
| Shear Strength, MPa | 400 to 690 | |
| 120 to 140 |
| Tensile Strength: Ultimate (UTS), MPa | 580 to 1180 | |
| 160 to 220 |
| Tensile Strength: Yield (Proof), MPa | 230 to 860 | |
| 80 to 130 |
Thermal Properties
| Latent Heat of Fusion, J/g | 290 | |
| 350 |
| Maximum Temperature: Mechanical, °C | 710 | |
| 130 |
| Melting Completion (Liquidus), °C | 1450 | |
| 600 |
| Melting Onset (Solidus), °C | 1400 | |
| 490 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 990 |
| Thermal Conductivity, W/m-K | 16 | |
| 78 |
| Thermal Expansion, µm/m-K | 17 | |
| 27 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 2.4 | |
| 11 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.7 | |
| 58 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 15 | |
| 12 |
| Density, g/cm3 | 7.8 | |
| 1.7 |
| Embodied Carbon, kg CO2/kg material | 3.0 | |
| 22 |
| Embodied Energy, MJ/kg | 43 | |
| 160 |
| Embodied Water, L/kg | 150 | |
| 990 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 86 to 250 | |
| 4.2 to 7.7 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 140 to 1870 | |
| 69 to 170 |
| Stiffness to Weight: Axial, points | 14 | |
| 15 |
| Stiffness to Weight: Bending, points | 25 | |
| 69 |
| Strength to Weight: Axial, points | 21 to 42 | |
| 26 to 34 |
| Strength to Weight: Bending, points | 20 to 32 | |
| 38 to 46 |
| Thermal Diffusivity, mm2/s | 4.2 | |
| 45 |
| Thermal Shock Resistance, points | 12 to 25 | |
| 9.5 to 13 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 8.3 to 9.7 |
| Carbon (C), % | 0 to 0.080 | |
| 0 |
| Chromium (Cr), % | 18 to 20 | |
| 0 |
| Copper (Cu), % | 0 | |
| 0 to 0.030 |
| Iron (Fe), % | 66.5 to 74 | |
| 0 to 0.0050 |
| Magnesium (Mg), % | 0 | |
| 88.7 to 91.2 |
| Manganese (Mn), % | 0 to 2.0 | |
| 0.15 to 0.5 |
| Nickel (Ni), % | 8.0 to 10.5 | |
| 0 to 0.0020 |
| Nitrogen (N), % | 0 to 0.1 | |
| 0 |
| Phosphorus (P), % | 0 to 0.045 | |
| 0 |
| Silicon (Si), % | 0 to 0.75 | |
| 0 to 0.1 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 |
| Zinc (Zn), % | 0 | |
| 0.35 to 1.0 |