Optical and spectral properties | |
---|---|
Transmission range | 160‐3500
|
Refractive index @ 486 nm | nf = 1,4632 |
Refractive index @ 588 nm | nd = 1,4586
|
Refractive index @ 656 nm | nc = 1,4565
|
Reflection losses in % at 1 surface | 7,9 @ 3 µm
|
dN/dT in 1/K | 9,1 · 10-6 @ 1064 nm
|
Physical properties | |
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Density in g/cm3 | 2,203
|
Crystal structure | amorphous |
Bubbles/ Inclusions | none |
Total metallic impurities in ppm | 25 ‐ 30 |
OH- Content in ppm | 400 ‐ 500 |
Specific heat capacity in J/(kg · K) | 703
|
Thermal conductivity in W/(m · K) | 1,38
|
Thermal expansion in 1/K | 0,55· 10-6
|
Softening point in °C | 1730
|
Annealing point | 1180 |
Strain point | 1075 |
Max. service temperature (continuous) in °C | 1150
|
Max. service temperature (limited time) in °C | 1300
|
Dielectric constant @ 1kHz | a = 10 |
Dielectric strength, kV/cm @ 20°C |
250 ‐ 400 |
Young's Modulus (E) in Gpa @ 25°C | 73
|
Shear Modulus (G) in GPa @ 25°C | 31
|
Bulk Modulus (K) in GPa @25 °C | 36,9 |
Rupture Modulus in MPa @ 25°C | 50
|
Apparent elastic limit in MPa | 55
|
Poisson's ratio @ 25 °C | 0,17 |
Compressive strength in GPa | 1,1 |
Tensile strength in MPa | 50 |
Knoop hardness in kg/mm²2 | 500 |
Spectral properties | |
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sample thickness: 2 mm |