Materials / Compare
Glass vs. Plastic ABS (bulk/injection)
Compare Glass vs. Plastic ABS (bulk/injection) 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) | 45MPasourcetypical, tensile stress at yield 23 °C |
| Ultimate tensile strength | 41MPasourcetypical mean surface tensile stress at fracture (MOR), 60 s load, weathered, 50% breakage probability | not sourced |
| Flexural strength | 41MPasourcemean MOR (same value as tensile) | 65MPasourcetypical, 23 °C |
| Elongation at break | not sourced | 10%sourcenominal strain at break, 23 °C |
| Young's modulus (stiffness) | 72GPasourcetypical31.3x stiffer | 2.3GPasourcetypical |
| Density | 2,500kg/m³sourcetypical | 1,040kg/m³sourcetypical2.4x lighter |
| Strength to weight | 16.4kN·m/kg | 43.3kN·m/kg2.64x higher |
| Stiffness to weight | 28.8MN·m/kg13x higher | 2.21MN·m/kg |
| Poisson's ratio | 0.22sourcetypical | 0.39sourcetypical, ABS family (Covestro Part and Mold Design guide, Table 3-1) |
| Shear modulus | 29.5GPa35.7x stiffer in shear | 0.827GPa |
| Bulk modulus | 42.9GPa | 3.48GPa |
| Speed of sound | 5,367m/s | 1,487m/s |
| Thermal | ||
| Thermal conductivity | 0.937W/m·Ksourcetypical at 75 F | 0.17W/m·Ksourcetypical |
| Thermal expansion | 8.3µm/m·Ksourcetypical, 75-575 F | 80–110µm/m·Ksourcerange |
| 100 mm part over a 50 °C swing | 41.5µm growth11.4x less | 475µm growth |
| 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/m2.35x more resistant | 21.4W/m |
| Max service temperature | 511°Csourcestrain point (ASTM C336) - stress-relaxation onset, not a rated service limit | 94°CsourceHDT 1.8 MPa (annealed 4 h/80 °C) |
| Values for | Annealed soda-lime-silica float glass, Pilkington North America Technical Bulletin ATS-129 (04/2025) | INEOS Styrolution Terluran GP-22 general-purpose injection-molding ABS, ISO typical values (TDS revision 08/01/2022) |
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.
Questions
Is Glass stronger than Plastic ABS (bulk/injection)?
Plastic ABS (bulk/injection) is stronger: its yield strength is 45 MPa against tensile strength 41 MPa for Glass (10%).
Which is lighter, Glass or Plastic ABS (bulk/injection)?
Plastic ABS (bulk/injection) is lighter: 1,040 kg/m³ against 2,500 kg/m³ for Glass.
Which is stiffer, Glass or Plastic ABS (bulk/injection)?
Glass is stiffer: Young's modulus 72 GPa against 2.3 GPa for Plastic ABS (bulk/injection), so the same part in Glass deflects less under the same load.
Which is lighter for the same job, Glass or Plastic ABS (bulk/injection)?
For the same stiffness or strength: Glass is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate; Plastic ABS (bulk/injection) is lighter for a strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Glass | Plastic ABS (bulk/injection) |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 13x heavier |
| Stiff beam (bending) | lighter | 2.33x heavier |
| Stiff panel or plate | lighter | 31% heavier |
| Strong rod or tie | 2.64x heavier | lighter |
| Strong beam | 2.56x heavier | lighter |
| Strong panel or plate | 2.52x 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, Glass or Plastic ABS (bulk/injection)?
Glass conducts heat better: 0.937 W/m·K against 0.17 W/m·K for Plastic ABS (bulk/injection).
Which expands less with temperature?
Glass expands less: 8.3 µm/m·K against 95 µm/m·K for Plastic ABS (bulk/injection).