Materials / Compare
Glass vs. Steel AISI 1045
Compare Glass vs. Steel AISI 1045 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) | 531MPasourceproducer-stated, cold drawn |
| Ultimate tensile strength | 41MPasourcetypical mean surface tensile stress at fracture (MOR), 60 s load, weathered, 50% breakage probability | 627MPasourceproducer-stated, cold drawn |
| Flexural strength | 41MPasourcemean MOR (same value as tensile) | not sourced |
| Elongation at break | not sourced | 12%sourcein 2 in (50.8 mm) |
| Young's modulus (stiffness) | 72GPasourcetypical | 210GPasourcetypical2.92x stiffer |
| Density | 2,500kg/m³sourcetypical3.12x lighter | 7,800kg/m³sourcetypical |
| Strength to weight | 16.4kN·m/kg | 68.1kN·m/kg4.15x higher |
| Stiffness to weight | 28.8MN·m/kg7% higher | 26.9MN·m/kg |
| Poisson's ratio | 0.22sourcetypical | 0.3sourcetypical |
| Shear modulus | 29.5GPa | 80.8GPa2.74x stiffer in shear |
| Bulk modulus | 42.9GPa | 175GPa |
| Speed of sound | 5,367m/s | 5,189m/s |
| Thermal | ||
| Thermal conductivity | 0.937W/m·Ksourcetypical at 75 F | 40–45W/m·Ksourcetypical range, ambient |
| Thermal expansion | 8.3µm/m·Ksourcetypical, 75-575 F | 12µm/m·Ksourcetypical, 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 | 460–480J/kg·Ksourcetypical range, 50/100 °C |
| Heats up and cools (diffusivity) | 0.426mm²/s | 11.6mm²/s27.2x faster |
| Thermal shock resistance | 50.1W/m | 6,269W/m125x 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 1045 cold drawn bar (Niagara LaSalle) for mechanical; Ovako C45 (lists 'SAE 1045' as a similar designation) for physical constants |
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 1045?
Steel AISI 1045 is stronger: its yield strength is 531 MPa against tensile strength 41 MPa for Glass (13x).
Which is lighter, Glass or Steel AISI 1045?
Glass is lighter: 2,500 kg/m³ against 7,800 kg/m³ for Steel AISI 1045.
Which is stiffer, Glass or Steel AISI 1045?
Steel AISI 1045 is stiffer: Young's modulus 210 GPa against 72 GPa for Glass, so the same part in Steel AISI 1045 deflects less under the same load.
Which is lighter for the same job, Glass or Steel AISI 1045?
For the same stiffness or strength: Glass is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate; Steel AISI 1045 is lighter for a strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Glass | Steel AISI 1045 |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 7% heavier |
| Stiff beam (bending) | lighter | 1.83x heavier |
| Stiff panel or plate | lighter | 2.18x heavier |
| Strong rod or tie | 4.15x heavier | lighter |
| Strong beam | 1.77x heavier | lighter |
| Strong panel or plate | 15% 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 Steel AISI 1045?
Steel AISI 1045 conducts heat better: 42.5 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 1045.