Fused Silica vs. PTFE
Fused silica and PTFE belong to fundamentally different material chemistries. Fused silica is a ceramic material, while PTFE is polymeric. Therefore, their performance will be even more dissimilar than would be suggested by the difference in properties. There are 13 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 fused silica and the bottom bar is PTFE.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 1100 | |
| 6.9 to 24 |
| Flexural Strength, MPa | 67 | |
| 13 to 50 |
| Tensile Strength: Ultimate (UTS), MPa | 50 | |
| 13 to 25 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 1080 | |
| 260 to 270 |
| Melting Onset (Solidus), °C | 1900 | |
| 330 to 340 |
| Thermal Conductivity, W/m-K | 1.4 | |
| 0.24 to 0.65 |
| Thermal Expansion, µm/m-K | 0.5 | |
| 110 to 120 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 3.8 | |
| 2.1 to 2.4 |
| Electrical Dissipation At 1 MHz | 0.00011 | |
| 0.00017 to 0.050 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 14 | |
| 2.0 to 18 |
Otherwise Unclassified Properties
| Density, g/cm3 | 2.2 | |
| 2.1 to 2.3 |
Common Calculations
| Strength to Weight: Axial, points | 6.3 | |
| 1.7 to 3.2 |
| Strength to Weight: Bending, points | 14 | |
| 5.7 to 8.7 |