Page 174 - Chalcogenide Glasses for Infrared Optics

150 Cha pte r S i x

Property Amtir 1 Amtir 2 Amtir 3 Amtir 4 Amtir 5 Amtir 6 C1
Composition Ge-Ae- As-Se Ge-Sb-Se As-Se As-Se As-S As-Se-Te
Se
Transmission 0.7–12 1.0–14 1.0–12 1.0–12 1.0–12 0.6–8 1.2–14
range (µm)
Ref. index at 2.4981 2.7691 2.6027 2.6431 2.7398 2.3807 2.8051
10 µm
∆N/∆T (°C × 72 5 91 −23 < 1 < 1 31
–6
10 ) (5 µm)
Knoop 170 110 150 84 87 109 110
hardness
Thermal 12 22.4 14 27 23.7 21.6 23
expansion ×
–6
10 /°C
Thermal condx 6 5.3 5.3 5.3 5.7 4 5.2
[cal/(g · s ·
–4
°C)10 ]
Specific heat 0.072 0.068 0.066 0.086 0.076 0.109 0.062
[cal/(g · °C)]
Density 4.4 4.66 4.67 4.49 4.51 3.2 4.69
3
(g/cm )
Rupture 2700 2500 2500 2358 2400 2400 2500
modulus (psi)
Young’s 3.2 2.65 3.1 2.2 2.56 2.3 1.8
modulus
(× 10 psi)
6
Shear modulus 1.3 1.03 1.2 0.85 1.01 0.94 1.03
6
(× 10 psi)
Poisson’s ratio 0.27 0.29 0.26 0.297 0.279 0.24 0.29
Softening 405 188 295 131 170 210 154
point (°C)
Glass 368 167 278 103 143 187 133
transition
temp. T (°C)
g
Upper-use 300 150 250 90 130 150 120
temp. (°C)
Dispersion
values
3–5 µm 202 176 159 186 175 155 148
8–12 µm 109 162 110 235 172 196

TABLE 6.4 Comparison of IR Transmitting Glasses Produced by AMI