Alpha Quartz vs. Fused Silica
Alpha quartz belongs to the non-glass optical ceramics classification, while fused silica belongs to the glass and glass-ceramics. There are 14 material properties with values for both materials. Properties with values for just one material (12, in this case) are not shown.
For each property being compared, the top bar is alpha quartz and the bottom bar is fused silica.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 91 | |
| 73 |
| Knoop Hardness | 740 | |
| 570 |
| Poisson's Ratio | 0.13 | |
| 0.17 |
| Shear Modulus, GPa | 31 | |
| 31 |
Thermal Properties
| Melting Onset (Solidus), °C | 1590 | |
| 1900 |
| Specific Heat Capacity, J/kg-K | 720 | |
| 720 |
| Thermal Conductivity, W/m-K | 8.5 | |
| 1.4 |
| Thermal Expansion, µm/m-K | 9.5 | |
| 0.5 |
Otherwise Unclassified Properties
| Density, g/cm3 | 2.7 | |
| 2.2 |
| Light Transmission Range, µm | 0.13 to 3.4 | |
| 0.16 to 3.5 |
| Refractive Index | 1.6 | |
| 1.5 |
Common Calculations
| Stiffness to Weight: Axial, points | 19 | |
| 18 |
| Stiffness to Weight: Bending, points | 57 | |
| 63 |
| Thermal Diffusivity, mm2/s | 4.4 | |
| 0.85 |