Materials / Compare
Glass vs. Plastic TPU
Compare Glass vs. Plastic TPU strength, stiffness, weight and thermal properties.
| Try it on a partA sample part to run stress or thermal on, free in your browser | Open in LessCAD | Open in LessCAD |
|---|---|---|
| Mechanical | ||
| Yield strength | not given (tensile used) | not given (tensile used) |
| Ultimate tensile strength | 41MPasourcetypical mean surface tensile stress at fracture (MOR), 60 s load, weathered, 50% breakage probability | 23.7MPasourcetypical, stress at break |
| Flexural strength | 41MPasourcemean MOR (same value as tensile) | 4.1MPasourcetypical |
| Elongation at break | not sourced | not sourced |
| Young's modulus (stiffness) | 72GPasourcetypical1,075x stiffer | 0.067GPasourcetypical |
| Density | 2,500kg/m³sourcetypical | 1,220kg/m³sourcetypical2.05x lighter |
| Strength to weight | 16.4kN·m/kg | 19.4kN·m/kg18% higher |
| Stiffness to weight | 28.8MN·m/kg524x higher | 0.0549MN·m/kg |
| Poisson's ratio | 0.22sourcetypical | not sourced |
| Shear modulus | 29.5GPa | not sourced |
| Bulk modulus | 42.9GPa | not sourced |
| Speed of sound | 5,367m/s | 234m/s |
| Thermal | ||
| Thermal conductivity | 0.937W/m·Ksourcetypical at 75 F | not sourced |
| Thermal expansion | 8.3µm/m·Ksourcetypical, 75-575 F | not sourced |
| 100 mm part over a 50 °C swing | 41.5µm growth | not sourced |
| Specific heat | 880J/kg·Ksourcetypical at 75 F | not sourced |
| Heats up and cools (diffusivity) | 0.426mm²/s | not sourced |
| Thermal shock resistance | 50.1W/m | not sourced |
| Melting point | not sourced | 217°Csourcetypical |
| Max service temperature | 511°Csourcestrain point (ASTM C336) - stress-relaxation onset, not a rated service limit | 50.3°CsourceHDT 0.455 MPa (printed specimens) |
| Values for | Annealed soda-lime-silica float glass, Pilkington North America Technical Bulletin ATS-129 (04/2025) | Ultimaker TPU 95A, 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 (file v5.00), April 29, 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 TPU is 3D printed: its properties depend on build direction and print settings; these are typical values.
Questions
Is Glass stronger than Plastic TPU?
Glass is stronger: its tensile strength is 41 MPa against 23.7 MPa for Plastic TPU (1.73x).
Which is lighter, Glass or Plastic TPU?
Plastic TPU is lighter: 1,220 kg/m³ against 2,500 kg/m³ for Glass.
Which is stiffer, Glass or Plastic TPU?
Glass is stiffer: Young's modulus 72 GPa against 0.067 GPa for Plastic TPU, so the same part in Glass deflects less under the same load.
Which is lighter for the same job, Glass or Plastic TPU?
For the same stiffness or strength: Glass is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate; Plastic TPU is lighter for a strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Glass | Plastic TPU |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 524x heavier |
| Stiff beam (bending) | lighter | 16x heavier |
| Stiff panel or plate | lighter | 5x heavier |
| Strong rod or tie | 18% heavier | lighter |
| Strong beam | 42% heavier | lighter |
| Strong panel or plate | 1.56x 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).