AgBr PC-EXT
Grade
PC-EXT = extruded polycrystalline rod / IR fiber preform
Choose when the material must be cold-extruded into unclad far-IR fibres or flexible light guides.
Values for the PC-EXT condition
Other AgBr tempers and conditions
AgBr is listed in 3 conditions; see the grade overview at AgBr.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SC-OPTDefault Optical-grade single crystal | Choose for windows, ATR prisms and lenses where lowest scatter and best IR transmission are needed. | — | 20 | 40 | — | 1 W/m·K |
Hot-pressed / forged polycrystalline blank | Choose for large, low-cost windows and gaskets where slight scatter is acceptable. | — | 24 | 20 | 10 HV | 1 W/m·K |
PC-EXTThis page Extruded polycrystalline rod / IR fiber preform | Choose when the material must be cold-extruded into unclad far-IR fibres or flexible light guides. | — | 28 | 50 | 9 HV | 1 W/m·K |
What is AgBr PC-EXT?
AgBr PC-EXT is AgBr in the PC-EXT grade — choose when the material must be cold-extruded into unclad far-IR fibres or flexible light guides. AgBr PC-EXT has a tensile strength of 28 MPa (4.06 ksi), weaker than 81% of glass grades. Elongation at break is 50% and the elastic modulus is 20 GPa (2.9 Msi). AgBr PC-EXT has a density of 6.47 g/cm³ (0.234 lb/in³), heavier than 98% of glass grades. It melts at 432°C (810 °F). SC-OPT is the default condition FabDigit quotes; PC-EXT is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 50%, better than 102% of glass grades
Limitations
- Heavy — 6.47 g/cm³ (0.234 lb/in³), worse than 98% of glass grades
- Low stiffness — 20 GPa (2.9 Msi), worse than 93% of glass grades
- Limited service temperature — 150°C (302 °F), worse than 92% of glass grades
- High embodied carbon — 70 kg CO₂/kg, worse than 90% of glass grades
- Hard to polish — 55/100, worse than 85% of glass grades
AgBr PC-EXT properties
Typical room-temperature values for AgBr PC-EXT; 15 are specific to this condition. Other listed values are AgBr reference data and may not represent this condition. Bars are the position among glass grades.
Physical5
AgBr PC-EXT has a density of 6.47 g/cm³ (0.234 lb/in³), heavier than 98% of glass grades. It melts at 432°C (810 °F).
Mechanical11
AgBr PC-EXT has a tensile strength of 28 MPa (4.06 ksi), weaker than 81% of glass grades. Elongation at break is 50% and the elastic modulus is 20 GPa (2.9 Msi).
Thermal5
AgBr PC-EXT is rated for continuous service to 150°C (302 °F). It conducts heat at 1.1 W/m·K (0.607 BTU/hr·ft·°F), worse than 73% of glass grades. Thermal expansion is 33 µm/m·K (18.3 µin/in·°F).
Electrical3
AgBr PC-EXT has an electrical resistivity of 500,000 Ω·m.
Chemical & Environmental2
Corrosion resistance is very good (70/100), worse than 58% of glass grades.
Sustainability4
Producing a kilogram of AgBr PC-EXT takes about 900 MJ of energy and emits 70 kg of CO₂ — more than 89% of glass grades. Typical recycled content is 40%.
Manufacturability2
AgBr PC-EXT's machinability is poor (25/100, better than 63% of glass grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with AgBr PC-EXT
Is AgBr easy to machine?
Very soft and prone to smearing on the tool — use single-point diamond turning or light-load diamond sawing. Cutting fluids must be free of ammonia and sulfides, and aluminium or copper fixtures must not be used.
Can AgBr be welded?
Not weldable; components are cold-welded by press or extrusion plastic deformation, or bonded with optical cement.
Can AgBr be formed, bent or molded?
Flows plastically at room temperature, so it can be cold extruded into IR fibre or hot pressed into window blanks. Forming temperature is typically 100–250 °C, with silver-plated or graphite dies.
What surface finishes work on AgBr?
Wet polish with very fine diamond slurry in anhydrous or neutral media. Store polished parts away from light; AR coating is normally applied to offset the high reflection loss from n≈2.25.
AgBr 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 |
|---|---|---|
| Agstoichiometric AgBr, M = 187.77 g/mol | 57.2 – 57.7 | 57.45 |
| impuritiestypical 4N–5N raw salt; Cl, I, Fe, Cu, Pb controlled at ppm level | ≤ 0.05 | 0.01 |
| Br | ≥ 42.3 (balance) | — |
AgBr PC-EXT — frequently asked
What is AgBr PC-EXT used for?
AgBr PC-EXT is typically used for far-IR fiber optics, IR windows in humid/marine settings and radiometry components. In short: transmits to 35 µm; non-hygroscopic silver halide; cold-extrudable into fibre.
What is the tensile strength of AgBr PC-EXT?
AgBr PC-EXT has a typical tensile strength of 28 MPa (4.06 ksi) — weaker than 81% of glass grades. Strength varies by condition: see the 3 listed tempers.
Is AgBr PC-EXT easy to machine?
Not especially — machinability is rated poor (25/100, better than 63% of glass grades). Very soft and prone to smearing on the tool — use single-point diamond turning or light-load diamond sawing. Cutting fluids must be free of ammonia and sulfides, and aluminium or copper fixtures must not be used.
Can AgBr PC-EXT be welded?
Not weldable; components are cold-welded by press or extrusion plastic deformation, or bonded with optical cement.
What surface finishes work on AgBr PC-EXT?
Wet polish with very fine diamond slurry in anhydrous or neutral media. Store polished parts away from light; AR coating is normally applied to offset the high reflection loss from n≈2.25.
Can AgBr PC-EXT be formed, bent or molded?
Flows plastically at room temperature, so it can be cold extruded into IR fibre or hot pressed into window blanks. Forming temperature is typically 100–250 °C, with silver-plated or graphite dies.
What is the maximum service temperature of AgBr PC-EXT?
AgBr PC-EXT is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- CRC Handbook of Chemistry and Physics — silver bromide physical data — CRC Press (2021)
- Handbook of Optical Constants of Solids (Palik) — AgBr — Academic Press (1998)
- Infrared window & ATR crystal material property tables (silver halides) — IR optics manufacturers (2023)
- Elastic constants of alkali/silver halides — Landolt-Börnstein (1992)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.