Materials / Compare
Magnesium AZ91D vs. Plastic ABS
Compare Magnesium AZ91D vs. Plastic ABS strength, stiffness, weight and thermal properties.
| Try it on a partA bracket to run stress or thermal on, free in your browser | Open in LessCAD | Open in LessCAD |
|---|---|---|
| Mechanical | ||
| Yield strength | 150MPasourcetypical, 0.2% tensile yield, ambient temperature | 38.1MPasourcetypical |
| Ultimate tensile strength | 230MPasourcetypical, ambient temperature | 38.1MPasourcetypical, peak stress (= stress at yield) |
| Flexural strength | not sourced | 61.1MPasourcetypical |
| Elongation at break | 3%sourcetypical, ambient temperature | 4.6%sourcetypical |
| Young's modulus (stiffness) | 45GPasourcetypical22.9x stiffer | 1.96GPasourcetypical |
| Density | 1,810kg/m³sourcetypical | 1,100kg/m³sourcetypical1.65x lighter |
| Strength to weight | 82.9kN·m/kg2.39x higher | 34.6kN·m/kg |
| Stiffness to weight | 24.9MN·m/kg13.9x higher | 1.78MN·m/kg |
| Poisson's ratio | 0.35sourcebase material: AZ91C casting (MIL-HDBK-5J handbook physical constant) | 0.39sourcebase material: ABS family typical (Covestro Part and Mold Design guide, Table 3-1) |
| Shear modulus | 16.7GPa23.6x stiffer in shear | 0.706GPa |
| Bulk modulus | 50GPa | 2.97GPa |
| Speed of sound | 4,986m/s | 1,336m/s |
| Thermal | ||
| Thermal conductivity | 72W/m·Ksourcetypical | 0.17W/m·Ksourcebase material: INEOS Styrolution Terluran GP-22 injection-molding ABS, typical |
| Thermal expansion | 25µm/m·Ksourcetypical, temperature range not stated | 80–110µm/m·Ksourcebase material: INEOS Styrolution Terluran GP-22 injection-molding ABS, range |
| 100 mm part over a 50 °C swing | 125µm growth3.8x less | 475µm growth |
| Specific heat | 1,050J/kg·Ksourcetypical | not sourced |
| Heats up and cools (diffusivity) | 37.9mm²/s | not sourced |
| Thermal shock resistance | 6,240W/m294x more resistant | 21.2W/m |
| Melting point | 470–595°Csourcemelting range | not sourced |
| Glass transition | not sourced | 101°Csourcetypical |
| Max service temperature | not sourced | 86.6°CsourceHDT 0.455 MPa (printed specimens) |
| Values for | ELEKTRON AZ91D magnesium die-casting alloy, as cast; Magnesium Elektron datasheet 475 (7/01), typical properties; Poisson from MIL-HDBK-5J for AZ91C castings. | Ultimaker ABS, 3D-printed specimens, XY (flat); Ultimaker S5 Pro, engineering intent profile, 0.15 mm layer height, AA 0.4 print core, 100% infill, Cura 4.9, printed one-at-a-time, conditioned >=24 h at room temperature. TDS v5.00, April 20, 2022. |
Every value links to the document that states it. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.
Plastic ABS is 3D printed: its properties depend on build direction and print settings; these are typical values.
Questions
Is Magnesium AZ91D stronger than Plastic ABS?
Magnesium AZ91D is stronger: its yield strength is 150 MPa against 38.1 MPa for Plastic ABS (3.94x).
Which is lighter, Magnesium AZ91D or Plastic ABS?
Plastic ABS is lighter: 1,100 kg/m³ against 1,810 kg/m³ for Magnesium AZ91D.
Which is stiffer, Magnesium AZ91D or Plastic ABS?
Magnesium AZ91D is stiffer: Young's modulus 45 GPa against 1.96 GPa for Plastic ABS, so the same part in Magnesium AZ91D deflects less under the same load.
Which is lighter for the same job, Magnesium AZ91D or Plastic ABS?
For the same stiffness or strength: Magnesium AZ91D is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Magnesium AZ91D | Plastic ABS |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 13.9x heavier |
| Stiff beam (bending) | lighter | 2.91x heavier |
| Stiff panel or plate | lighter | 1.73x heavier |
| Strong rod or tie | lighter | 2.39x heavier |
| Strong beam | lighter | 1.52x heavier |
| Strong panel or plate | lighter | 21% heavier |
For the same stiffness or strength, mass scales with density over stiffness (or strength) raised to a power set by how the part is loaded: 1 for a rod in tension, 1/2 for a beam in bending, 1/3 for a panel (the standard material-selection indices).
Which conducts heat better, Magnesium AZ91D or Plastic ABS?
Magnesium AZ91D conducts heat better: 72 W/m·K against 0.17 W/m·K for Plastic ABS.
Which expands less with temperature?
Magnesium AZ91D expands less: 25 µm/m·K against 95 µm/m·K for Plastic ABS.