If you work in electrical engineering, manufacturing, or construction, you’ve likely heard of 110 copper. This pure copper alloy is a top choice for projects needing excellent conductivity and formability—but understanding its standards, properties, and best uses can be tricky. This guide breaks down everything you need to know, with real-world examples and actionable data.
1. Alloy Designation & Global Standards for 110 Copper
110 copper isn’t just a random number—it’s defined by strict international standards. Knowing these designations ensures you pick the right material for compliance and performance.
- UNS Designation: The most common label is C11000 (ETP) Copper, where “ETP” stands for Electrolytic Tough Pitch. This grade has a minimum copper content of 99.95%, making it ideal for electrical applications.
- ASTM Standards: ASTM B152/B187 sets specs for 110 copper sheets, strips, and plates. For rods, MIL-C-12166 is the go-to military standard for high-reliability projects like aerospace wiring.
- International Equivalents:
- Europe: ISO Cu-ETP CW004A
- Japan: JIS C1100 Rounded Copper (used widely in electronics manufacturing)
- China: GB/T 5231 T2 copper (a direct equivalent for electrical conductors)
- Key Requirements: All 110 copper grades must meet RoHS compliance (no hazardous substances) and have an oxygen content < 0.04% (a critical ETP requirement to avoid brittleness).
Example: A solar panel manufacturer in Germany would specify ISO Cu-ETP CW004A for their PV ribbons, while a U.S.-based company would use C11000 to meet ASTM B152 standards.
2. Mechanical & Physical Properties: Why 110 Copper Stands Out
110 copper’s properties make it versatile—from electrical conductors to heat sinks. Below is a clear breakdown of its key characteristics:
| Property | Value Range | Real-World Impact |
|---|---|---|
| Tensile Strength | 210–250 MPa | Can withstand stress in busbars without breaking |
| Electrical Conductivity | 45–50 % IACS | Transmits electricity efficiently (only slightly less than pure copper) |
| Thermal Conductivity | 385–400 W m⁻¹ K⁻¹ | Dissipates heat fast—perfect for heat-sink fins |
| Hardness | 70–90 HRB | Soft enough for bending, hard enough for durability |
| Elongation | 35–55 % in 50 mm | Bends easily into shapes like architectural gutters |
| Density | 8.89 g cm⁻³ | Heavy enough for stable lightning protection cables |
| Melting Point | 1083 °C | Withstands high temperatures in motor windings |
Example: A transformer maker uses 110 copper for windings because its 45–50 % IACS conductivity minimizes energy loss, and its 1083 °C melting point resists overheating.
3. Fabrication Processes for 110 Copper
Working with 110 copper requires knowing its limits—here’s how to shape it effectively:
- Cold Forming: 110 copper handles cold bending well, but follow bending radius guidelines (1–2× thickness) to avoid cracking. For example, a 2mm thick C11000 sheet needs a 2–4mm radius.
- Annealing: To soften the metal after cold working, use an annealing temperature of 370–650 °C. A manufacturer making deep-drawn electrical enclosures would anneal 110 copper at 500 °C to improve ductility.
- Machinability: With a machinability rating of 20 % (vs. 100% for free-cutting brass), 110 copper is slow to machine. Use sharp tools and coolants to prevent overheating.
- Special Processes:
- Deep-drawing: Ideal for making cups or connectors (common in PCB manufacturing).
- Spinning & hydroforming: Feasible for creating curved parts like waveguide components.
- Stress Relief: Use heat treatment cycles (e.g., 200 °C for 1 hour) to reduce internal stress after welding.
Tip: To prevent hydrogen embrittlement, avoid heating 110 copper in hydrogen-rich environments—this can cause the metal to crack.
4. Welding, Brazing & Joining 110 Copper
Joining 110 copper requires careful temperature control and the right materials. Here’s what works:
- GTAW (TIG) Welding: The most reliable method for 110 copper. For thick sections (over 6mm), use a preheat of 200–540 °C to ensure full fusion.
- Filler Metals: Use silicon-bronze ERCuSi-A for TIG welding—it bonds well and maintains conductivity.
- Brazing: Choose phosphorus-deoxidized brazing alloys to avoid oxidation. A refrigeration technician might braze 110 copper tubes with these alloys for leak-free joints.
- Other Methods:
- Electron Beam Welding (EBW): Works for precision parts like vacuum chamber gaskets.
- Resistance Spot Welding: Requires high current density (10,000–15,000 A/mm²) for strong joints in automotive components.
Important: After welding, test joint conductivity—a drop of more than 5% IACS means the joint needs rework.
5. Surface Treatments & Coatings for 110 Copper
Protect 110 copper from tarnish and improve its performance with these treatments:
- Tin Plating: Boosts solderability—used for PCB foil to ensure easy soldering of components.
- Silver Plating: Maintains high conductivity for RF shielding gaskets in telecom equipment.
- Nickel Underlayer: Acts as a corrosion barrier for 110 copper parts in marine environments.
- Chemical Treatments:
- Benzotriazole (BTA) Dip: Prevents oxidation—applied to coinage stock to keep it shiny.
- Electropolishing: Creates an ultra-smooth finish (Ra < 0.1 µm) for vacuum chamber parts.
- Decorative Finishes: Hot black oxide is used for architectural accents like flashing to match dark building exteriors.
Example: A jewelry maker uses electropolishing on 110 copper medallions to achieve a mirror-like shine (Ra < 0.1 µm).
6. Top Applications & Markets for 110 Copper
110 copper’s mix of conductivity, formability, and compliance makes it essential in these industries:
- Electrical:
- Busbar & electrical conductor strips: Transmit power in factories and data centers.
- PCB foil: Connects components on circuit boards.
- Solar PV ribbon interconnects: Links solar cells in panels.
- Electronics:
- Waveguide & RF shielding gaskets: Block interference in 5G equipment.
- Transformer & motor windings: Efficiently transfer energy.
- Construction:
- Lightning protection cables: Safely channel lightning to the ground.
- Architectural flashing & gutters: Resist corrosion and look sleek.
- Specialty:
- Heat-sink fins & base plates: Cool CPUs and power supplies.
- Vacuum chamber gaskets: Maintain airtight seals in scientific equipment.
- Coinage & medallion stock: Durable and easy to engrave.
Yigu Technology’s Perspective on 110 Copper
At Yigu Technology, we’ve seen 110 copper become a staple in our electrical component projects. Its C11000 (ETP) designation ensures consistency across global orders, and its 45–50 % IACS conductivity meets our clients’ efficiency needs. We often recommend tin-plated 110 copper for PCB applications, as it balances solderability and cost. For clients in harsh environments, we pair 110 copper with a nickel underlayer to prevent corrosion. Overall, 110 copper’s versatility makes it a reliable choice for both standard and custom projects.
FAQ About 110 Copper
- What’s the difference between 110 copper (C11000) and pure copper?
Pure copper has slightly higher conductivity (≈58% IACS), but 110 copper (C11000) is more affordable and still offers excellent performance (45–50% IACS). 110 copper also has better formability for bending and welding. - Can 110 copper be used outdoors?
Yes—with the right coating. A nickel underlayer or chromate conversion coating (Alodine) protects it from rain and humidity. Many builders use coated 110 copper for outdoor gutters and flashing. - Is 110 copper RoHS-compliant?
Most grades are, but always check the supplier’s documentation. Reputable manufacturers produce RoHS-compliant 110 copper that meets global environmental standards (no lead, mercury, or other hazardous substances).
