Materials / Compare
Glass vs. Steel AISI 1018
Compare Glass vs. Steel AISI 1018 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) | 372MPasourceproducer-stated, cold drawn |
| Ultimate tensile strength | 41MPasourcetypical mean surface tensile stress at fracture (MOR), 60 s load, weathered, 50% breakage probability | 441MPasourceproducer-stated, cold drawn |
| Flexural strength | 41MPasourcemean MOR (same value as tensile) | not sourced |
| Elongation at break | not sourced | 15%sourcein 2 in (50.8 mm) |
| Young's modulus (stiffness) | 72GPasourcetypical | 200GPasourcebase material: AISI 1025 plain carbon steel (MIL-HDBK-5J design value; ASTM A108 bar is the cold-finished carbon-steel bar spec that also covers 1018) |
| Density | 2,500kg/m³sourcetypical | 7,861kg/m³sourcebase material: AISI 1025 plain carbon steel (MIL-HDBK-5J design value; ASTM A108 bar is the cold-finished carbon-steel bar spec that also covers 1018) |
| Strength to weight | 16.4kN·m/kg | 47.3kN·m/kg2.89x higher |
| Stiffness to weight | 28.8MN·m/kg13% higher | 25.4MN·m/kg |
| Poisson's ratio | 0.22sourcetypical | 0.32sourcebase material: AISI 1025 plain carbon steel (MIL-HDBK-5J design value; ASTM A108 bar is the cold-finished carbon-steel bar spec that also covers 1018) |
| Shear modulus | 29.5GPa | 75.7GPa2.57x stiffer in shear |
| Bulk modulus | 42.9GPa | 185GPa |
| Speed of sound | 5,367m/s | 5,043m/s |
| Thermal | ||
| Thermal conductivity | 0.937W/m·Ksourcetypical at 75 F | 51.9W/m·Ksourcebase material: AISI 1025 plain carbon steel (MIL-HDBK-5J design value; ASTM A108 bar is the cold-finished carbon-steel bar spec that also covers 1018) |
| Thermal expansion | 8.3µm/m·Ksourcetypical, 75-575 F | 12µm/m·Ksourcebase material: unalloyed carbon steel, Ovako family table (S275JR, 'none alloyed structural steels', C <= 0.21%); mean 20-300 °C |
| 100 mm part over a 50 °C swing | 41.5µm growth45% less | 60µm growth |
| Specific heat | 880J/kg·Ksourcetypical at 75 F | 486J/kg·Ksourcebase material: AISI 1025 plain carbon steel (MIL-HDBK-5J design value; ASTM A108 bar is the cold-finished carbon-steel bar spec that also covers 1018) |
| Heats up and cools (diffusivity) | 0.426mm²/s | 13.6mm²/s31.9x faster |
| Thermal shock resistance | 50.1W/m | 5,473W/m109x more resistant |
| Max service temperature | 511°Csourcestrain point (ASTM C336) - stress-relaxation onset, not a rated service limit | not sourced |
| Values for | Annealed soda-lime-silica float glass, Pilkington North America Technical Bulletin ATS-129 (04/2025) | AISI 1018 cold drawn bar (Niagara LaSalle, cold-finished bar producer) |
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 Steel AISI 1018?
Steel AISI 1018 is stronger: its yield strength is 372 MPa against tensile strength 41 MPa for Glass (9.07x).
Which is lighter, Glass or Steel AISI 1018?
Glass is lighter: 2,500 kg/m³ against 7,861 kg/m³ for Steel AISI 1018.
Which is stiffer, Glass or Steel AISI 1018?
Steel AISI 1018 is stiffer: Young's modulus 200 GPa against 72 GPa for Glass, so the same part in Steel AISI 1018 deflects less under the same load.
Which is lighter for the same job, Glass or Steel AISI 1018?
For the same stiffness or strength: Glass is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong panel or plate; Steel AISI 1018 is lighter for a strong rod or tie, strong beam.
| Part that must be | Glass | Steel AISI 1018 |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 13% heavier |
| Stiff beam (bending) | lighter | 1.89x heavier |
| Stiff panel or plate | lighter | 2.24x heavier |
| Strong rod or tie | 2.89x heavier | lighter |
| Strong beam | 38% heavier | lighter |
| Strong panel or plate | lighter | 4% 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, Glass or Steel AISI 1018?
Steel AISI 1018 conducts heat better: 51.9 W/m·K against 0.937 W/m·K for Glass.
Which expands less with temperature?
Glass expands less: 8.3 µm/m·K against 12 µm/m·K for Steel AISI 1018.