Materials / Compare
Nickel Inconel 718 vs. Plastic PMMA
Compare Nickel Inconel 718 vs. Plastic PMMA 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 | 1,207MPasourcetypical, 1.0 in. hot-rolled bar, 0.2% offset | not given (tensile used) |
| Ultimate tensile strength | 1,389MPasourcetypical, 1.0 in. bar | 80MPasourcetypical, 23 °C |
| Compressive strength | not sourced | 110MPasourcecompressive yield stress, typical |
| Flexural strength | not sourced | 115MPasourcetypical |
| Elongation at break | 20%sourcetypical, 1.0 in. bar | 5.5%sourcetypical |
| Young's modulus (stiffness) | 200GPasourcetypical, 21 °C, annealed + aged | 3.3GPasourcetypical, short-term |
| Density | 8,221kg/m³sourcenominal, annealed and aged | 1,190kg/m³sourcetypical |
| Strength to weight | 147kN·m/kg2.18x higher | 67.2kN·m/kg |
| Stiffness to weight | 24.3MN·m/kg8.77x higher | 2.77MN·m/kg |
| Poisson's ratio | 0.294sourcetypical, 21 °C, annealed + aged | 0.37sourcetypical |
| Shear modulus | 77.3GPa64.2x stiffer in shear | 1.2GPa |
| Bulk modulus | 162GPa | 4.23GPa |
| Speed of sound | 4,932m/s | 1,665m/s |
| Thermal | ||
| Thermal conductivity | 11.4W/m·Ksourcetypical, 21 °C, annealed + aged (calculated from resistivity per footnote a) | 0.19W/m·Ksourcetypical |
| Thermal expansion | 13.2µm/m·Ksourcetypical, mean 21-93 °C, annealed + aged | 70µm/m·Ksource0-50 °C |
| 100 mm part over a 50 °C swing | 66µm growth5.3x less | 350µm growth |
| Specific heat | 435J/kg·Ksourcetypical, 21 °C | 1,470J/kg·Ksourcetypical |
| Heats up and cools (diffusivity) | 3.19mm²/s29.3x faster | 0.109mm²/s |
| Thermal shock resistance | 3,680W/m88.8x more resistant | 41.5W/m |
| Melting point | 1,260–1,336°Csourcemelting range | not sourced |
| Max service temperature | 704°Csourceupper use temperature stated by producer | 80°Csourcemax. permanent service temperature |
| Values for | INCONEL alloy 718, standard grade, 1750 °F/1 hr anneal + 1325 °F/8 hr F.C. to 1150 °F aged; Special Metals bulletin SMC-045 typical values | Röhm PLEXIGLAS GS 0F00 cast acrylic sheet, typical values at 23 °C / 50 % RH (Röhm Technical Information Ref. No. 211-1) |
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.
Questions
Is Nickel Inconel 718 stronger than Plastic PMMA?
Nickel Inconel 718 is stronger: its yield strength is 1,207 MPa against tensile strength 80 MPa for Plastic PMMA (15.1x).
Which is lighter, Nickel Inconel 718 or Plastic PMMA?
Plastic PMMA is lighter: 1,190 kg/m³ against 8,221 kg/m³ for Nickel Inconel 718.
Which is stiffer, Nickel Inconel 718 or Plastic PMMA?
Nickel Inconel 718 is stiffer: Young's modulus 200 GPa against 3.3 GPa for Plastic PMMA, so the same part in Nickel Inconel 718 deflects less under the same load.
Which is lighter for the same job, Nickel Inconel 718 or Plastic PMMA?
For the same stiffness or strength: Nickel Inconel 718 is lighter for a stiff rod or tie (tension), stiff beam (bending), strong rod or tie; Plastic PMMA is lighter for a stiff panel or plate, strong beam, strong panel or plate.
| Part that must be | Nickel Inconel 718 | Plastic PMMA |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 8.77x heavier |
| Stiff beam (bending) | lighter | 13% heavier |
| Stiff panel or plate | 1.76x heavier | lighter |
| Strong rod or tie | lighter | 2.18x heavier |
| Strong beam | 13% heavier | lighter |
| Strong panel or plate | 1.78x heavier | lighter |
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, Nickel Inconel 718 or Plastic PMMA?
Nickel Inconel 718 conducts heat better: 11.4 W/m·K against 0.19 W/m·K for Plastic PMMA.
Which expands less with temperature?
Nickel Inconel 718 expands less: 13.2 µm/m·K against 70 µm/m·K for Plastic PMMA.