What Makes a Thick-Walled C10100 Tube Different
A thick-walled round tube in C10100 oxygen-free electronic copper is produced from the same 99.99% minimum purity base metal as thin-wall capillary, but with a wall-to-diameter ratio that turns the tube into a structural as well as a conductive element. The heavy section keeps the bore dimensionally stable under internal pressure and external clamping loads, damps vibration in vacuum systems and provides enough material for thread cutting, grooving and press-fitting without losing wall integrity.
Because the grade is virtually oxygen-free, with oxygen typically at or below 0.001%, the tube tolerates the elevated temperatures used in brazing, glass-to-metal sealing and vacuum bake-out without hydrogen embrittlement. That is the property that separates it from tough pitch copper in electronics service.
Key Performance Characteristics
Electrical conductivity of 101% IACS or higher, so current-carrying components generate the minimum possible resistive loss.
Thermal conductivity around 398–401 W/(m·K), enough to move heat away from a sealed electronics package by conduction alone.
Extremely low oxygen content, which removes the risk of hydrogen embrittlement and makes the tube suitable for reducing and vacuum atmospheres.
Excellent cold and hot workability, allowing bending, flaring, swaging, stamping and deep drawing without intermediate annealing.
Strong corrosion resistance in air, fresh water, inert gases and mildly corrosive media, together with non-magnetic behaviour that prevents interference in sensitive instruments.
Dimensions, Composition and Material Data
| Product Form | Thickness / Wall (mm) | Diameter / Width (mm) | Length (mm) |
|---|---|---|---|
| Round tube | 0.5–10 | Φ5–200 | 1000–6000 |
| Plate | 0.1–50 | 50–600 | 500–6000 |
| Strip | 0.05–3.0 | 10–300 | Coil, customised |
| Wire | - | Φ0.1–20 | Coil or straight |
Thick-wall tube can be supplied in straight lengths up to 6 m or in coiled form for smaller diameters, with custom wall thicknesses available above the standard range for pressure-retaining inserts and heavy-duty electrode carriers.
| Element | Content (%) |
|---|---|
| Cu | ≥99.99 |
| O | ≤0.0005 |
| Other impurities, total | ≤0.001 |
The grade also delivers a density of 8.94 g/cm³ and a melting point of 1083 °C, with electrical conductivity in the 101–103% IACS band and thermal conductivity between 398 and 401 W/(m·K).
| Property | Value |
|---|---|
| Density | 8.94 g/cm³ |
| Melting point | 1083 °C |
| Electrical conductivity | 101–103% IACS |
| Thermal conductivity | 398–401 W/(m·K) |
| Condition | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) |
|---|---|---|---|
| Annealed (O) | 200–220 | 50–70 | ≥45 |
| Hard temper (H) | 300–350 | 280–320 | 3–8 |
The annealed condition is used where the tube must be formed after delivery, while the hard temper is chosen for finished components such as waveguide sections, electrode holders and machined spacers that need stiffness and wear resistance rather than formability.
Applications in Electronics and Energy Equipment
Semiconductor lead frames and high-frequency coaxial conductors, where loss per unit length and signal stability both depend on purity.
Vacuum tube anodes, klystron bodies and fusion test reactor liners, where low outgassing and freedom from grain-boundary oxide are essential.
Superconducting magnet windings, laser cavity cooling components and accelerator beam-line hardware that must shed heat rapidly.
Precision instrument bushings, sealed feedthroughs and heavy-wall sleeves that are machined, threaded and brazed into assemblies.
Specification and Ordering Guidance
Thick-wall tube is normally ordered to ASTM B75/B75M for general seamless tube, ASTM B88 where water service is involved, or ASTM B280 where refrigeration cleanliness applies; European projects frequently reference EN 1057 for supply piping and EN 13348 for medical gas and vacuum circuits. The enquiry should define the outside diameter, wall thickness, temper, length, end finish, concentricity and straightness limits, plus the test schedule and the certificate level required.
Parameters that most often cause disputes are concentricity on thick walls, internal cleanliness after machining, and straightness on long heavy lengths. Agreeing these three items in writing before rolling produces a component that assembles without rework.
Frequently Asked Questions
Q: Why specify a thick wall instead of a larger diameter thin tube?
A thick wall carries vibration and clamping loads without ovalising, gives enough material for machining threads or grooves, and keeps the bore stable under vacuum. A thin-wall tube of the same bore would deform first and lose its dimensional accuracy.
Q: Does a thick wall reduce electrical performance?
Only in mass, not in conductivity. The grade still delivers 101% IACS or better on the cross-section, so a thicker wall lowers total resistance for a given length rather than degrading it.
Q: Can thick-wall tube be bent after delivery?
In soft annealed temper, yes, with the appropriate bending radius and mandrel support. Hard temper tube should be machined or brazed into assemblies rather than formed.
Q: What cleanliness standard applies to electronics tube?
Orders usually reference an ASTM tube specification together with a defined residue or outgassing limit. The end use, whether vacuum, sealed module or RF cavity, determines the stringency.
Q: How are the tubes packed for export?
Heavy-wall tube is supplied in strapped bundles or wooden cases with end protection, moisture barrier wrapping and bundle identity tags carrying the heat number so that mill test reports remain traceable on site.
Q: Which temper gives the best machined finish?
Half-hard and hard temper stock usually machines to a cleaner surface than fully annealed material, because the reduced ductility limits smearing and built-up edge during turning.
