Barium fluoride, BaF2 crystal
BaF2is relatively hard but is highly sensitive to thermal shock. For its transmission range is 0.2 μm - 11 μm, the material is widely used for making optical windows, lenses and prisms in UV-IR spectra. Besides it can also be used as substrate for some applications. BaF2is less resistant to attack by water than CaF2. Pronounced water attack occurs at 500 °C, but in a dry environment the material can be used up to 800 °C. BaF2is grown by modified Bridgman technique. Maximum available size: Dia 200 mm x Thickness 50 mm. In addition, BaF2 is usually used as scintillator for gamma detection. It is the fastest scintillating crystals up to now.
BaF2 crystals have the following exceptional properties that make it a very important optics single crystal:
(1) High optical transmittance from the ultraviolet to the far-infrared spectrum region(0.18-12μm).
(2) Used for Optical prisms, lenses, wedges, windows, other optical components, and etc.
Main Specifications:
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Maximum Size
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Single Crystal: φ100×100 mm
Poly Crystal:φ200×100 mm (3 ~7 boundaries)
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Dimension Tolerance
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± 0.1mm
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Flatness Tolerance
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λ~ λ/10 at 632.8 nm over central 90% of edge dimensional
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Parallelism
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±1 arc sec ~ ±3 arc min
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Surface Quality (Scratch/Dig)
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10/5
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Physical and Optical Properties:
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Transmission Range (mm)
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0.15 ~12.5
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Refractive Index (within 0.26~12.00 mm)
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1.5122~1.3703
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Reflection Loss at 10.35 mm
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5.3% (2 surfaces)
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Absorption Coefficient at 6mm (cm-1)
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3.2×10-4
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Density (g/cm3)
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4.89 at 20°C
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Melting Point (°C)
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<1280
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Thermal Conductivity at 286K (Wm-1K-1)
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11.72
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Thermal Expansion at 273K (K-1)
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18.1×10-6
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Knoop Hardness
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82kg/mm2
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Hardness (Mho)
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3
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Specific Heat (J Kgm-1K-1)
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410
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Dielectric Constant at 1MHz
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7.33
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Elastic Coefficients
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C11= 89.2 C12 = 40.0 C44= 25.4
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Apparent Elastic Limit (Mpa)
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26.9 (3900psi)
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Possion Ratio
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0.343
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Solubility in 100g water at 23°C (g)
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0.17
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Crystal type
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cubic, Class m3m
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Cleavage
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(111)
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| Packing︰ | vacuum packing |
| specification︰ | Single Crystal: φ100×100 mm, Poly Crystal:φ200×100 mm (3 ~7 boundaries) |
| advantage︰ | High quality, Quickly delivery time, Good servise |
| Minimum Order︰ | 1 |
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