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Material BaF2 (Barium Fluoride)
Barium Fluoride is used for optical windows, lenses and prisms. The transmission range is 0.2 µm - 11 µm.
Barium fluoride is grown by vacuum Stockbarger technique. Polishing
is quicker than calcium fluoride using diamond pastes but is
less easy to obtain free of sleeks. Barium fluoride is less
resistant to attack by water than Calcium Fluoride. Pronounced
water attack occurs at 500 °C, but the material can be used
to 800 °C in a dry environment. The material is relatively hard
but is highly sensitive to thermal shock.
BASE PROPERTIES
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PARAMETER |
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VALUE |
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| OPTICAL |
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Transmission Range |
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0.13 to 10 microns |
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Refractive Index |
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1.4626 at 2.6 microns |
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Reflection Lossе |
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6.9% at 2.6 µm (2 surfaces) |
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Restrahlen Peak |
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47 microns |
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dn/dT |
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-15.2 x 10-6/oC |
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| PHYSICAL |
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Density |
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4.89 g/cm3 |
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Melting Point |
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1280 ° С |
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Thermal Conductivity |
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11.72 W/(m K) at 13 °C> |
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Thermal Expansion |
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18.1 x 10-6/°C at -100 to +200 °C |
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Hardness |
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Knoop 82 kg/mm2 with 500g indenter |
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Specific Heat Capacity |
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410 J/(kg K) at 27 °C |
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Dielectric Constant |
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7.33 at 2MHz |
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Young's Modulus (E) |
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53.07 GPa |
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Shear Modulus (G) |
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25.4 GPa |
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Bulk Modulus (K) |
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56.4 GPa |
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Elastic Coefficients |
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C11
= 89.2 MPa; C12 = 40.0 MPa;
C14=25.4 MPa |
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Apparent Elastic Limit |
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26.89 MPa |
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Poisson Ratio |
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0.343 |
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| CHEMICAL |
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Solubility |
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0.17g/100g water
at 23°C |
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Molecular Weight |
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175.36 |
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Class/Structure |
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Cubic (111) cleavage |
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REFRACTIVE INDEX
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Wavelength, µm |
0.26 |
0.30 |
0.36 |
0.48 |
0.85 |
3.24 |
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Refractive Index |
1.51 |
1.50 |
1.49 |
1.48 |
1.47 |
1.46 |
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Wavelength, µm |
5.14 |
6.50 |
8.00 |
8.60 |
9.20 |
9.80 |
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Refractive Index |
1.45 |
1.44 |
1.43 |
1.42 |
1.41 |
1.40 |
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Delivery
Maximum available size: 200 mm Dia x 50 mm Thk
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