ZnSe
also Irtran-4
ZnSe (Irtran-4) is a chemically vapour-deposited II-VI compound crystal transmitting 0.5–22 µm with very low absorption at 10.6 µm, which makes it the standard lens and window material for CO2 lasers.
Reference datasheet — ZnSe 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.
ZnSe tempers and conditions
ZnSe is supplied in 2 conditions, soft to hard.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Single-crystal ZnSe | Used as substrate and host for Cr²⁺:ZnSe / Fe²⁺:ZnSe mid-IR lasers and for lowest-scatter research optics; anisotropic, cleaves on {110}, expensive in large sizes. | 42 | 0 | 95 HV | 19 W/m·K | |
Multispectral / HIP-treated water-clear ZnSe | Pick when visible/NIR clarity and low scatter matter (0.4–14 µm multispectral windows, thermal imagers with visible channel); HIP coarsens grains so it is slightly weaker. | 48 | 0 | 100 HV | 18 W/m·K |
Supply forms, finishes and certifications
Ways ZnSe is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
CVDDefault | Chemical-vapour-deposited polycrystalline ZnSe | Coating |
What is ZnSe?
ZnSe (Irtran-4) is a chemically vapour-deposited II-VI compound crystal transmitting 0.5–22 µm with very low absorption at 10.6 µm, which makes it the standard lens and window material for CO2 lasers. It is stocked as CVD, multispectral CVD-MS and single-crystal blanks for flats, meniscus lenses, prisms and camera optics. The limits are mechanical and thermal: it is soft and brittle with a tendency to edge chipping, conducts 18 W/m·K and is rated to about 300 °C, and its dust is toxic because of the selenium. ZnS is the harder, lower-cost alternative where 10.6 µm absorption is not the governing requirement. ZnSe has a density of 5.27 g/cm³ (0.19 lb/in³), heavier than 90% of glass grades. It melts at 1,525°C (2,777 °F). ZnSe has a tensile strength of 50 MPa (7.25 ksi), stronger than 59% of glass grades. The elastic modulus is 67.2 GPa (9.75 Msi).
What is ZnSe used for?
- CO2 laser lenses/windows
- IR camera lenses
- multispectral optics
Advantages
- Conducts heat well — 18 W/m·K (10.4 BTU/hr·ft·°F), better than 85% of glass grades
- Easy to machine — 45/100, better than 85% of glass grades
Limitations
- Heavy — 5.27 g/cm³ (0.19 lb/in³), worse than 90% of glass grades
- Limited service temperature — 300°C (572 °F), worse than 80% of glass grades
- Low fracture toughness — 0.5 MPa·√m (0.455 ksi·√in), worse than 76% of glass grades
ZnSe properties
Typical room-temperature values; bars are the position among glass grades.
Physical5
ZnSe has a density of 5.27 g/cm³ (0.19 lb/in³), heavier than 90% of glass grades. It melts at 1,525°C (2,777 °F).
Mechanical10
ZnSe has a tensile strength of 50 MPa (7.25 ksi), stronger than 59% of glass grades. The elastic modulus is 67.2 GPa (9.75 Msi).
Thermal5
ZnSe is rated for continuous service to 300°C (572 °F). It conducts heat at 18 W/m·K (10.4 BTU/hr·ft·°F), better than 85% of glass grades. Thermal expansion is 7.1 µm/m·K (3.94 µin/in·°F).
Electrical3
ZnSe has an electrical resistivity of 1×10¹⁰ Ω·m.
Chemical & Environmental2
Corrosion resistance is good (55/100), worse than 74% of glass grades.
Manufacturability2
ZnSe'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. ZnSe is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ZnSe
Is ZnSe easy to machine?
Grind/core with diamond tooling under flood coolant or single-point diamond turn with light depth of cut; brittle and prone to edge chipping, and all dust/swarf is toxic (Se) so wet cutting with sealed extraction is mandatory.
Can ZnSe be welded?
Not weldable — a brittle ceramic; join only by optical contacting, epoxy bonding or mechanical mounting in compliant (RTV/retaining-ring) cells to avoid mount stress.
Can ZnSe be formed, bent or molded?
Formed to net shape by CVD deposition on mandrels, then HIP for multispectral grade; no plastic forming is possible, curved optics are generated and polished from blanks.
ZnSe 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 |
|---|---|---|
| Znstoichiometric ZnSe, 1:1 molar | 45 – 45.6 | 45.3 |
| impurities (C, Si, Fe, Cu, O)total metallic + carbon impurities in optical grade; low absorption depends on ppm-level control | ≤ 0.01 | 0 |
| Se | ≥ 54.4 (balance) |
What surface finishes work on ZnSe?
Pitch or polyurethane polish to <10 Å rms, then AR coat (ThF₄/YbF₃ or ZnS/YF₃ stacks) or DLC-protect the exposed face; keep bare surfaces dry and handle with gloves — hygroscopic-free but easily scratched.
Equivalent designations
Standards and trade names that resolve to ZnSe in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- Irtran-4
How much does ZnSe cost?
ZnSe is a high-cost glass ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
ZnSe — frequently asked
What is ZnSe used for?
ZnSe is typically used for CO2 laser lenses/windows, IR camera lenses and multispectral optics. In short: standard CO2 laser optic; low 10.6 µm absorption; brittle, selenium-bearing dust.
What is the tensile strength of ZnSe?
ZnSe has a typical tensile strength of 50 MPa (7.25 ksi) — stronger than 59% of glass grades. Strength varies by condition: see the 2 listed tempers.
Is ZnSe easy to machine?
Reasonably — machinability is rated fair (45/100, better than 85% of glass grades). Grind/core with diamond tooling under flood coolant or single-point diamond turn with light depth of cut; brittle and prone to edge chipping, and all dust/swarf is toxic (Se) so wet cutting with sealed extraction is mandatory.
Can ZnSe be welded?
Not weldable — a brittle ceramic; join only by optical contacting, epoxy bonding or mechanical mounting in compliant (RTV/retaining-ring) cells to avoid mount stress.
What surface finishes work on ZnSe?
Pitch or polyurethane polish to <10 Å rms, then AR coat (ThF₄/YbF₃ or ZnS/YF₃ stacks) or DLC-protect the exposed face; keep bare surfaces dry and handle with gloves — hygroscopic-free but easily scratched.
Can ZnSe be formed, bent or molded?
Formed to net shape by CVD deposition on mandrels, then HIP for multispectral grade; no plastic forming is possible, curved optics are generated and polished from blanks.
What is the maximum service temperature of ZnSe?
ZnSe is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does ZnSe cost?
ZnSe is a high-cost glass ($$$$), 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
- CVD ZnSe optical material datasheet — II-VI / Coherent (2022)
- Cleartran multispectral ZnSe properties — Dow / II-VI (2019)
- Handbook of Optical Constants of Solids — Academic Press (Palik, ed.) (1998)
- Handbook of Optical Materials — CRC Press (Weber) (2003)
- IR window and lens material property tables — Thorlabs / Edmund Optics technical notes (2023)
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.