Refractory Metal S-65 Extruded
Grade
ASTM B349 Grade S-65
Use where high longitudinal strength and stiffness in a slender section are needed (struts, tubes).
Values for the Extruded condition
Other S-65 tempers and conditions
S-65 is listed in 3 conditions; see the grade overview at S-65.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Stress-relieved / annealed (≈730–790 °C, vacuum) | Applied to machined optical and metrology parts to remove machining stresses and maximise long-term dimensional stability. | 205 | 320 | 5.5 | 108 HB | 41 % IACS |
Hot isostatic pressed | Choose for near-net shapes and the most isotropic properties in thick sections. | 240 | 365 | 5 | 120 HB | 40 % IACS |
ExtrudedThis page Extruded bar / tube | Use where high longitudinal strength and stiffness in a slender section are needed (struts, tubes). | 330 | 460 | 8 | 132 HB | 39 % IACS |
What is S-65 Extruded?
S-65 Extruded is S-65 in the Extruded grade — use where high longitudinal strength and stiffness in a slender section are needed (struts, tubes). S-65 Extruded has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 460 MPa (66.7 ksi) — stronger than 50% of refractory metal grades. Elongation at break is 8% and the elastic modulus is 303 GPa (43.9 Msi). S-65 Extruded has a density of 1.85 g/cm³ (0.0668 lb/in³), lighter than 96% of refractory metal grades. It melts at 1,287°C (2,349 °F).
Advantages
- Easy to machine — 42/100, better than 97% of refractory metal grades
- Lightweight — 1.85 g/cm³ (0.0668 lb/in³), better than 96% of refractory metal grades
- Conducts heat well — 205 W/m·K (118.4 BTU/hr·ft·°F), better than 91% of refractory metal grades
- High electrical conductivity — 39 % IACS, better than 91% of refractory metal grades
Limitations
- High embodied carbon — 250 kg CO₂/kg, worse than 89% of refractory metal grades
- Needs corrosion protection — 45/100, worse than 86% of refractory metal grades
- Limited formability — 12/100, worse than 84% of refractory metal grades
- Difficult to weld — 20/100, worse than 79% of refractory metal grades
- Limited ductility — 8%, worse than 75% of refractory metal grades
S-65 Extruded properties
Typical room-temperature values for S-65 Extruded; 21 are specific to this condition. Other listed values are S-65 reference data and may not represent this condition. Bars are the position among refractory metal grades.
Physical3
S-65 Extruded has a density of 1.85 g/cm³ (0.0668 lb/in³), lighter than 96% of refractory metal grades. It melts at 1,287°C (2,349 °F).
Mechanical13
S-65 Extruded has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 460 MPa (66.7 ksi) — stronger than 50% of refractory metal grades. Elongation at break is 8% and the elastic modulus is 303 GPa (43.9 Msi).
Thermal6
S-65 Extruded is rated for continuous service to 500°C (932 °F). It conducts heat at 205 W/m·K (118.4 BTU/hr·ft·°F), better than 91% of refractory metal grades. Thermal expansion is 11.3 µm/m·K (6.28 µin/in·°F).
Electrical3
S-65 Extruded conducts electricity at 39 % IACS, better than 91% of refractory metal grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 86% of refractory metal grades.
Sustainability4
Producing a kilogram of S-65 Extruded takes about 4,000 MJ of energy and emits 250 kg of CO₂ — more than 89% of refractory metal grades. Typical recycled content is 15%.
Manufacturability8
S-65 Extruded's machinability is fair (42/100, better than 97% of refractory metal grades); weldability poor (20/100); formability not recommended (12/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with S-65 Extruded
Is S-65 easy to machine?
Machines like a hard, abrasive cast iron with carbide/PCD tooling and low feeds; all dust and coolant must be captured (Be sensitisation/CBD hazard), and a light chemical etch removes the damaged twinned surface layer.
Can S-65 be welded?
Fusion welding is difficult (hot cracking, coarse grain); electron-beam welding with Al-Si filler, Ag-based brazing or mechanical/adhesive joining are preferred.
Can S-65 be formed, bent or molded?
Cold formability is essentially nil due to the hcp structure; forming, bending and deep drawing are done warm (400–800 °C), often with steel cladding.
What surface finishes work on S-65?
Not anodizable in the aluminium sense — use chromate conversion coating, electroless nickel or Ni plating; optical surfaces are diamond-turned/polished after etching and often nickel-plated.
S-65 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 |
|---|---|---|
| BeOberyllium oxide content, low-oxide grade | ≤ 1 | 0.7 |
| Fe | ≤ 0.08 | 0.05 |
| C | ≤ 0.1 | 0.06 |
| Al | ≤ 0.06 | 0.03 |
| Mg | ≤ 0.06 | 0.02 |
| Si | ≤ 0.06 | 0.02 |
| other metallic impurities (each)per element | ≤ 0.04 | — |
| Beassay, minimum | ≥ 99 (balance) | — |
S-65 Extruded — frequently asked
What is S-65 Extruded used for?
S-65 Extruded is typically used for precision optical mirrors, space telescope structures and high-reliability aerospace brackets. In short: most ductile beryllium grade; very low BeO content; aerospace-standard Be grade.
What is the yield strength of S-65 Extruded?
S-65 Extruded has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 460 MPa (66.7 ksi) — stronger than 50% of refractory metal grades. Strength varies by condition: see the 3 listed tempers.
Is S-65 Extruded easy to machine?
Not especially — machinability is rated fair (42/100, better than 97% of refractory metal grades). Machines like a hard, abrasive cast iron with carbide/PCD tooling and low feeds; all dust and coolant must be captured (Be sensitisation/CBD hazard), and a light chemical etch removes the damaged twinned surface layer.
Can S-65 Extruded be welded?
Not readily — weldability is rated poor (20/100). Fusion welding is difficult (hot cracking, coarse grain); electron-beam welding with Al-Si filler, Ag-based brazing or mechanical/adhesive joining are preferred.
What surface finishes work on S-65 Extruded?
Not anodizable in the aluminium sense — use chromate conversion coating, electroless nickel or Ni plating; optical surfaces are diamond-turned/polished after etching and often nickel-plated.
Can S-65 Extruded be formed, bent or molded?
Cold formability is essentially nil due to the hcp structure; forming, bending and deep drawing are done warm (400–800 °C), often with steel cladding.
What is the maximum service temperature of S-65 Extruded?
S-65 Extruded is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM B349/B349M — Beryllium grades (S-65 chemistry and mechanical requirements) — ASTM International (2020)
- Structural beryllium grades S-65 / S-200F product data — Materion Beryllium & Composites (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (Beryllium) — ASM International (1990)
- Beryllium: Chemistry, Metallurgy and Applications — technical literature (2009)
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.