Potassium Bromide vs. Lithium Fluoride
Both potassium bromide and lithium fluoride are non-glass optical ceramics.
For each property being compared, the top bar is potassium bromide and the bottom bar is lithium fluoride.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 24 | |
| 120 |
| Poisson's Ratio | 0.17 | |
| 0.27 |
| Shear Modulus, GPa | 7.0 | |
| 52 |
Thermal Properties
| Melting Onset (Solidus), °C | 730 | |
| 870 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 1560 |
| Thermal Conductivity, W/m-K | 4.8 | |
| 12 |
| Thermal Expansion, µm/m-K | 39 | |
| 32 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 4.9 | |
| 9.0 |
| Electrical Dissipation At 1 MHz | 0.00020 | |
| 0.00020 |
Otherwise Unclassified Properties
| Density, g/cm3 | 2.8 | |
| 2.6 |
| Light Transmission Range, µm | 0.22 to 26 | |
| 0.12 to 6.5 |
| Refractive Index | 1.8 | |
| 1.4 |
Common Calculations
| Stiffness to Weight: Axial, points | 4.7 | |
| 24 |
| Stiffness to Weight: Bending, points | 35 | |
| 62 |
| Thermal Diffusivity, mm2/s | 3.9 | |
| 2.9 |