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ASTM B187 · H02 Half-Hard · UNS C10100
Oxygen-free electronic copper. The grade aerospace, defense, and nuclear drawings specify by name. Immune to hydrogen embrittlement. 120° bend tested per lot. No deviation request needed.
Product overview
Available sizes — thickness × width (inches)
| T↓/W→ | 3/4" | 1" | 1¼" | 1½" | 2" | 2½" | 3" | 3½" | 4" | 5" | 6" |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/8" | ● | ● | |||||||||
| 3/16" | ● | ● | ● | ● | ● | ● | ● | ||||
| 1/4" | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||
| 3/8" | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● |
| 1/2" | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● |
| 5/8" | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||
| 3/4" | ● | ● | ● | ● | ● | ● | ● |
Cross-section 80–2,000 mm². Max width 170 mm. Weight (lb/ft) = T × W × 3.884. Custom sizes on request.
Physical constants
Copper grade selection for busbar
Every busbar salesperson will tell you conductivity is the same across grades. They are right. That is not the point. The point is oxygen — and what it does under heat, in a hydrogen furnace, under tight-radius forming, or inside a laser weld pool.
| Criterion | C11000 ETP · Tough Pitch |
C10200 OF · Oxygen-Free |
C10100 — Our Base Metal OFE · Oxygen-Free Electronic |
|---|---|---|---|
Oxygen content The one number everything else follows |
200–400 ppm Cu₂O throughout the matrix |
≤ 10 ppm | ≤ 5 ppm Essentially oxide-free |
Minimum copper |
99.90% Cu | 99.95% Cu | 99.99% Cu — Four nines |
Conductivity at 20°C |
100–101% IACS | 101% IACS | 101% IACS or better |
Brazing & hydrogen furnace Reducing atmosphere under heat |
Susceptible — grain boundary cracking | Immune | Immune — bend-tested per lot |
Plating held through heat Hot-dip tin, reflow, later brazing |
Blistering risk | Good | Predictable — clean bright substrate |
Tight-radius forming Compact enclosures, 120° bends |
Surface cracking risk | Good | 120° verified — no cracking |
Laser & ultrasonic welding Battery and interconnect joints |
Porosity & spatter | Low porosity | Most repeatable |
Trace elements controlled Ag, As, Sb, Te, Pb, Zn, Fe, P |
Not bounded | Partly bounded | Eight elements bounded — per mill cert |
Drawings that mandate OFE Aerospace, defense, nuclear |
Not permitted | Usually accepted | Specified by name — no deviation needed |
Verdict |
Cut, drill, bolt and leave alone. Nothing above is a problem in still air at ambient. | A sound choice. Satisfies most oxygen-free callouts at 10 ppm. | Specify when the bar will be brazed, plated, formed tight, or laser welded — or when the drawing simply will not accept anything else. |
Typical applications
Power infrastructure
Energy storage & e-mobility
Data centers & aerospace
How it's made
Busbar starts as rod. Rod starts as cathode. The entire chain runs under controlled atmosphere to keep oxygen below 5 ppm — from melt to final cut length.
Grade 1 cathode (ASTM B115) is melted and cast upward through a water-cooled graphite die in an inert atmosphere. The upward solidification direction naturally excludes impurities and keeps oxygen below 5 ppm without flux or deoxidant addition. The result is a fully recrystallized OFE rod with a clean, oxide-free surface — ready for extrusion or drawing without further conditioning.
OFE rod enters the KONFORM continuous rotary extrusion wheel. Friction drives the material into a die where it is formed to the final cross-section in a single pass — no heating cycle, no head/tail crop. The process produces a fully recrystallized, soft-temper bar with dimensional consistency over its entire length. For busbar, subsequent drawing and straightening bring the profile to H02 half-hard temper with straightness ≤3 mm over 2.4 m.
Every lot undergoes visual inspection for surface defects, dimensional verification of thickness and width, temper verification by hardness and tensile sampling, 120° bend test with no-crack confirmation, and chemical analysis against the eight bounded trace elements of C10100. Mill test report available per lot. Cut to length. Packaged in wooden box or plastic wrap. Delivered to plant.
Quality assurance
Ordering