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FUSED SILICA (7059)
DESCRIPTION
| Fused Silica (7059) offers the same thermal, physical and mechanical properties which are typical of all fused silica. This material is ideal for optical reference flats, test plates, structural members and high temperature view ports where fused silica properties such as low CTE are desired. It is available in substrate and optical (higher homogeneity) grades. |
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SHEET SIZES
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Up to about 18" x 25", depending on variables.
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AVAILABLE THICKNESSES
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Wide variety - per quotation
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PROPERTIES
| Refractive Index: | nd (λ = 589 nm) = 1.4584 |
| Dispersion: | ν = 67.8 |
| Transmission (estimated at 2 mm thick): |
@ 185 nm 88.2% | @ 230 nm 91.1% |
@390 nm 92.7%
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| @ 200 nm 89.4% | @ 310 nm 92% |
400-1240 nm 92%+
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| Transmittance at varying levels from 1250 nm to 4400 nm | |||
| Bubble Inclusion Class No. 0 upon request: |
(Max. cross-section of any single bubble or inclusion = 0.004") |
| (Total cross-section of inclusions /100cm3 = 0.03 mm2) |
| Homogeneity: | Substrate Grade | Not specified |
| Optical Grade F | 5 x 10-6 (higher grades available on request) |
| Thermal: | CTE (0 - 200°C) | 5.7 x 10-7/°C |
| Thermal Conductivity (25°C) | 1.38 W/m°C | |
| Specific Heat (25°C) | 0.177 cal/gm°C | |
| Thermal Diffusivity (25°C) | 8.4 x 10-3 cm2/sec. |
| Electrical: | Dielectric Constant (25°C, 1 KHz) | 3.79 |
| Dielectric Loss Factor (25°C, 1 KHz) | 0.00002 |
| Physical: |
Density
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2.202 gm/cm3
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Softening point
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1585°C
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Strain point
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990°C
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Annealing point
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1075°C | |
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Elastic (Young's) modulus
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7.3 x 104 MPa @ 25°C
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APPLICATIONS
| Fused silica can be used where resistance to radiation darkening is required, such as in space or as long-term passive energy collectors. |