CuBevalues describe: C17200 TH04
Vacuum equipment & componentsBig science (accelerators, light sources, public fusion)Quantum hardware
Why it wins
The vacuum spring metal: contact fingers, RF gaskets and spring seals, anti-vibration clamps. Conductive, non-magnetic, keeps temper after modest bakes.
Why not the alternative
Stainless springs are poor conductors; phosphor bronze relaxes hot.
Watch out
Beryllium content: no grinding or abrading without controls.
Properties
The values below are candidate: compiled from the sources named, not yet individually validated.
Provisional provenance: ASM Handbook: properties, corrosion, heat treatment; Kurt J. Lesker materials notes.
Wet cleaning
| Recipe | degrease and DI rinse only; wet handling of every machined surface |
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| Forbidden | dry grinding or abrasive blasting: beryllium dust |
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| Limit | exposure control, and never bake past the ageing temperature |
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Vacuum and outgassing
| Outgassing, unbaked (10 h) | 2e-9 mbar·L/s/cm² |
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| Outgassing, baked | 1e-11 mbar·L/s/cm² |
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| Vapour pressure | Be evaporation negligible; the hazard is dust, not vapour |
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Temperature
| Bake, assembled | 300 °C |
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| Vacuum degas | 500 °C |
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| Metallurgical limit | age 315–345 °C; over-ageing kills the spring |
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Thermal
| CTE | 17 ppm/K |
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| Thermal conductivity | 105 W/m·K |
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| Specific heat | 420 J/kg·K |
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| Emissivity | 0.05 |
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| Melting / softening | 865–955 °C |
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Mechanical
| Strength | 1000–1200 ys MPa |
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| Tensile | 1300 MPa |
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| Elongation | 3–5 % |
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| Young's modulus | 128 GPa |
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| Hardness | 350–400 HV |
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| Density | 8.25 g/cm3 |
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Electrical and magnetic
| Relative permeability | ~1.0 non-magnetic |
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| Resistivity | 7.6 µΩ·cm |
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Engineering
| Corrosion | good |
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| Joining | brazed or mechanically retained |
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| Process notes | the non-magnetic spring metal; RF fingers and contacts |
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| Availability and cost | stock, licensed machining |
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Grades
| C17200 (2 percent Be), age hardened | maximum strength fingers and springs |
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| C17510 (NiBe) | higher conductivity, lower strength |
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Sources · 1
- Materion CuBe alloy guide
← The Matter