CaF2
also Irtran-3
CaF2 is a cubic fluorite single crystal transmitting from 0.13 to 10 µm with low dispersion and a low refractive index; hot-pressed polycrystalline material is sold as Irtran-3.
Reference datasheet — CaF2 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
CaF2 tempers and conditions
CaF2 is supplied in 3 conditions, soft to hard.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
VUV/Excimer | Choose the lithography and excimer-laser grade when transmission from 0.13 µm, very low fluorescence and stress birefringence, and resistance to radiation-induced colour centres are required. | 37 | 0 | 165 HV | 10 W/m·K | |
IR-grade single crystal | Use the lower-cost infrared blank for FTIR windows and IR lenses working from 0.25 to 9 µm, accepting uncontrolled absorption and fluorescence at the UV end. | 37 | 0 | 165 HV | 10 W/m·K | |
Poly | Pick the hot-pressed polycrystal for large domes needing higher strength and thermal-shock resistance than single crystal; grain-boundary scatter lowers UV and long-wave transmission. | 205 HV | — |
Supply forms, finishes and certifications
Ways CaF2 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
UVDefault | UV-grade single crystal | Grade option |
What is CaF2?
CaF2 is a cubic fluorite single crystal transmitting from 0.13 to 10 µm with low dispersion and a low refractive index; hot-pressed polycrystalline material is sold as Irtran-3. Engineers specify it for UV lithography lenses, 193 nm excimer laser optics and broadband spectroscopic windows, and it is stocked as grown boules, sawn blanks, windows, lenses and prisms in UV, VUV-193, IR and POLY-HP conditions. It cleaves on {111}, is slightly water-soluble and sensitive to thermal shock, with a maximum service temperature of 800 °C. Where deep-UV range is not required, fused silica is cheaper and more durable. CaF2 has a density of 3.18 g/cm³ (0.115 lb/in³), heavier than 58% of glass grades. It melts at 1,418°C (2,584 °F). CaF2 has a tensile strength of 37 MPa (5.37 ksi), weaker than 70% of glass grades. The elastic modulus is 75.8 GPa (11 Msi).
What is CaF2 used for?
- UV lithography lenses
- excimer laser optics
- spectroscopic windows
- IR windows
Advantages
- Easy to machine — 45/100, better than 85% of glass grades
- High service temperature — 800°C (1,472 °F), better than 81% of glass grades
- Conducts heat well — 9.7 W/m·K (5.6 BTU/hr·ft·°F), better than 78% of glass grades
Limitations
- Needs corrosion protection — 45/100, worse than 84% of glass grades
- Low fracture toughness — 0.33 MPa·√m (0.3 ksi·√in), worse than 81% of glass grades
- Hard to polish — 60/100, worse than 81% of glass grades
CaF2 properties
Typical room-temperature values; bars are the position among glass grades.
Physical5
CaF2 has a density of 3.18 g/cm³ (0.115 lb/in³), heavier than 58% of glass grades. It melts at 1,418°C (2,584 °F).
Mechanical10
CaF2 has a tensile strength of 37 MPa (5.37 ksi), weaker than 70% of glass grades. The elastic modulus is 75.8 GPa (11 Msi).
Thermal5
CaF2 is rated for continuous service to 800°C (1,472 °F). It conducts heat at 9.7 W/m·K (5.6 BTU/hr·ft·°F), better than 78% of glass grades. Thermal expansion is 18.9 µm/m·K (10.5 µin/in·°F).
Electrical3
CaF2 has an electrical resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental2
Corrosion resistance is fair (45/100), worse than 84% of glass grades.
Manufacturability2
CaF2's machinability is fair (45/100, better than 85% of glass grades).
Common Calculations4
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the glass family
Yield strength against density for every glass grade FabDigit runs. CaF2 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with CaF2
Is CaF2 easy to machine?
Grind with diamond wheels at low contact pressure or finish by single-point diamond turning, keeping loads light to avoid edge chipping along the {111} cleavage planes. Use anhydrous oil-based coolant only; water-based fluids are not permitted.
Can CaF2 be welded?
Not weldable; mount with elastomeric retaining rings, low-stress cementing or optical contact, since assembly stress induces birefringence.
Can CaF2 be formed, bent or molded?
Boules are grown in vacuum from high-purity CaF₂ powder with an oxygen scavenger by the Bridgman–Stockbarger crucible-descent method and then annealed to relieve stress. Polycrystalline parts are produced by hot pressing.
CaF2 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Castoichiometric CaF2 | 51 – 51.4 | 51.33 |
| Fmetals <50 ppm; UV/excimer grade: O, Ce, Na, K <1-5 ppm | ≥ 48.6 (balance) |
What surface finishes work on CaF2?
Rough-grind first, then polish on pitch laps with cerium oxide or alumina. Finish with an MgF₂ or multilayer UV/IR anti-reflection coating to raise transmission and protect against moisture.
Equivalent designations
Standards and trade names that resolve to CaF2 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- Irtran-3
How much does CaF2 cost?
CaF2 is a high-cost glass ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
CaF2 — frequently asked
What is CaF2 used for?
CaF2 is typically used for UV lithography lenses, excimer laser optics, spectroscopic windows and IR windows. In short: broadest UV-IR transmission; lowest dispersion fluoride crystal; standard 193 nm optic.
What is the tensile strength of CaF2?
CaF2 has a typical tensile strength of 37 MPa (5.37 ksi) — weaker than 70% of glass grades. Strength varies by condition: see the 3 listed tempers.
Is CaF2 easy to machine?
Reasonably — machinability is rated fair (45/100, better than 85% of glass grades). Grind with diamond wheels at low contact pressure or finish by single-point diamond turning, keeping loads light to avoid edge chipping along the {111} cleavage planes. Use anhydrous oil-based coolant only; water-based fluids are not permitted.
Can CaF2 be welded?
Not weldable; mount with elastomeric retaining rings, low-stress cementing or optical contact, since assembly stress induces birefringence.
What surface finishes work on CaF2?
Rough-grind first, then polish on pitch laps with cerium oxide or alumina. Finish with an MgF₂ or multilayer UV/IR anti-reflection coating to raise transmission and protect against moisture.
Can CaF2 be formed, bent or molded?
Boules are grown in vacuum from high-purity CaF₂ powder with an oxygen scavenger by the Bridgman–Stockbarger crucible-descent method and then annealed to relieve stress. Polycrystalline parts are produced by hot pressing.
What is the maximum service temperature of CaF2?
CaF2 is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does CaF2 cost?
CaF2 is a high-cost glass ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- Calcium Fluoride (CaF2) optical material datasheet — Crystran Ltd (2023)
- Engineered Materials Handbook Vol.4 — Ceramics and Glasses — ASM International (1991)
- Handbook of Optical Constants of Solids — Academic Press (Palik ed.) (1998)
- Calcium Fluoride for excimer laser and lithography optics — Corning Advanced Optics / Hellma Materials (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.