Fused Silica (FS)

Material
Properties
Optical 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
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
sample thickness: 2 mm