Materials / Compare
Aluminum vs. Plastic PLA
Compare Aluminum vs. Plastic PLA 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 | 276MPasourcetypical, 0.2% offset, .500 in dia specimen | 52.5MPasourcetypical |
| Ultimate tensile strength | 310MPasourcetypical | 52.5MPasourcetypical, peak stress (= stress at yield) |
| Flexural strength | not sourced | 96.8MPasourcetypical |
| Elongation at break | 17%sourcetypical, in 4D, 0.500 in dia specimen | 7.8%sourcetypical |
| Young's modulus (stiffness) | 68.3GPasourcetypical21x stiffer | 3.25GPasourcetypical |
| Density | 2,700kg/m³sourcenominal | 1,240kg/m³sourcetypical |
| Strength to weight | 102kN·m/kg2.41x higher | 42.3kN·m/kg |
| Stiffness to weight | 25.3MN·m/kg9.65x higher | 2.62MN·m/kg |
| Poisson's ratio | 0.33sourcetypical (handbook physical constant) | not sourced |
| Shear modulus | 25.7GPa | not sourced |
| Bulk modulus | 67GPa | not sourced |
| Speed of sound | 5,030m/s | 1,619m/s |
| Thermal | ||
| Thermal conductivity | 167W/m·Ksourcetypical, 20 °C | 0.13W/m·Ksourcebase material: NatureWorks Ingeo biopolymer, amorphous sheet, 25 °C |
| Thermal expansion | 23.6µm/m·Ksourcetypical, mean 20-100 °C | not sourced |
| 100 mm part over a 50 °C swing | 118µm growth | not sourced |
| Specific heat | 896J/kg·Ksourcetypical, at 100 °C | 1,200J/kg·Ksourcebase material: NatureWorks Ingeo biopolymer, amorphous sheet, 25 °C |
| Heats up and cools (diffusivity) | 69mm²/s790x faster | 0.0874mm²/s |
| Thermal shock resistance | 19,159W/m | not sourced |
| Melting point | 582–652°Csourcesolidus-liquidus | 152°Csourcetypical |
| Glass transition | not sourced | 59.1°Csourcetypical |
| Max service temperature | not sourced | 58.8°CsourceHDT 0.455 MPa (printed specimens) |
| Values for | 6061-T6/T651, Kaiser Aluminum typical properties (sheet, coil & plate datasheet); Poisson from MIL-HDBK-5J | Ultimaker PLA, 3D-printed specimens, XY (flat) orientation; 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 dated 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 PLA is 3D printed: its properties depend on build direction and print settings; these are typical values.
Questions
Is Aluminum stronger than Plastic PLA?
Aluminum is stronger: its yield strength is 276 MPa against 52.5 MPa for Plastic PLA (5.26x).
Which is lighter, Aluminum or Plastic PLA?
Plastic PLA is lighter: 1,240 kg/m³ against 2,700 kg/m³ for Aluminum.
Which is stiffer, Aluminum or Plastic PLA?
Aluminum is stiffer: Young's modulus 68.3 GPa against 3.25 GPa for Plastic PLA, so the same part in Aluminum deflects less under the same load.
Which is lighter for the same job, Aluminum or Plastic PLA?
For the same stiffness or strength: Aluminum 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 | Aluminum | Plastic PLA |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 9.65x heavier |
| Stiff beam (bending) | lighter | 2.11x heavier |
| Stiff panel or plate | lighter | 27% heavier |
| Strong rod or tie | lighter | 2.41x heavier |
| Strong beam | lighter | 39% heavier |
| Strong panel or plate | lighter | 5% 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, Aluminum or Plastic PLA?
Aluminum conducts heat better: 167 W/m·K against 0.13 W/m·K for Plastic PLA.