|
| |
Refractive Index |
nF (486nm) = 1.4632; nd (588nm) = 1.4586; nC (656nm) = 1.4565 |
| |
for two surfaces
at 400nm – 7.0%; at 588nm – 6.8%; | |
| |
Index of Absorption |
10 x 10-6 cm-1 at 1 microns |
| |
dN/dT |
+11.9 X 10-6/°C |
| |
dN/dµ = 0 |
1.3µm |
| |
Birefringence Constant |
3.61 nm/cm |
| |
Abbe Constant |
67.6 |
| |
Fluorescence |
Upon excitation at 242 nm the material displays blue fluorescence. |
| |
Impurity Content |
Total metallic impurities: 25 - 30 ppm |
| |
OH- Content |
400 - 500 ppm |
| |
Density |
2.203 g/cm3 |
| |
Thermal Conductivity |
1.38 Wm-1K-1 |
| |
Specific Heat Capacity |
703 J Kg-1K-1 |
| |
Coefficient of Expansion |
0.55 x 10-6 /oC |
| |
Softening Point |
1730oC (3146oF) |
| |
Annealing Point |
1180oC (2156oF) |
| |
Strain Point |
1075oC (1967oF) |
| |
Max. Service Temperature |
1150oC (2102oF) - continuous, 1300oC (2372oF) - limited time |
| |
Dielectric Constant |
3.91 at 1kHz |
| |
Dielectric Strength |
250-400 kV/cm at 20oC |
| |
Young's Modulus |
73 GPa at 25oC |
| |
Shear Modulus |
31 GPa at 25oC |
| |
Rupture Modulus |
50 MPa at 25oC |
| |
Bulk Modulus |
36.9 GPa at 25oC |
| |
Poisson Ratio |
0.17 at 25oC |
| |
Knoop Hardness |
500 kg/mm2 |
| |
Compressive Strength |
1.1 GPa |
| |
Tensile Strength |
50 MPa |
| |
Apparent Elastic Limit |
55MPa (7980 psi) |
| |
Molecular Weight |
28.09 |
| |
Class/Structure |
Amorphous glass |
| |
Chemical Stability |
High resistance to water and acids (except hydrofluoric). |
