Alpha Quartz vs. Mullite
Alpha quartz belongs to the non-glass optical ceramics classification, while mullite belongs to the oxide-based engineering ceramics. There are 10 material properties with values for both materials. Properties with values for just one material (18, in this case) are not shown.
For each property being compared, the top bar is alpha quartz and the bottom bar is mullite.
Metric UnitsUS Customary Units
Material Properties
| Density, g/cm3 | 2.7 | |
| 2.7 to 3.0 |
| Elastic (Young's, Tensile) Modulus, GPa | 91 | |
| 110 to 170 |
| Knoop Hardness | 740 | |
| 750 |
| Poisson's Ratio | 0.13 | |
| 0.25 |
| Specific Heat Capacity, J/kg-K | 720 | |
| 950 |
| Stiffness to Weight: Axial, points | 19 | |
| 22 to 31 |
| Stiffness to Weight: Bending, points | 57 | |
| 58 to 62 |
| Thermal Conductivity, W/m-K | 8.5 | |
| 3.5 to 11 |
| Thermal Diffusivity, mm2/s | 4.4 | |
| 1.4 to 3.7 |
| Thermal Expansion, µm/m-K | 9.5 | |
| 5.8 |