1″ Copper Square Bar (Alloy 110 – ETP) – High Conductivity Copper Bar

Copper Square Bar – Alloy 110 (C11000 / ETP) High-Conductivity Copper Bar

Our copper square bar is produced from Alloy 110 (C11000), the Electrolytic Tough Pitch grade of copper valued around the world for its exceptional electrical and thermal conductivity. Containing a minimum of 99.9% copper and rated at 100% IACS conductivity, this solid square bar provides a clean, uniform cross-section with crisp edges, making it easy to mount, clamp, machine and connect in electrical and mechanical assemblies.

The square profile offers a larger flat contact surface than a round bar of similar size, which is a clear advantage for bolted electrical joints, grounding systems and heat-transfer applications. Each product in this category is a specific side dimension and cut length, giving you the flexibility to buy only what you need.

Key Features and Benefits

• Solid square section in 99.9% pure copper (C11000 / ETP).
• Very high electrical conductivity (100% IACS minimum) for low-loss current transmission.
• Excellent thermal conductivity for heat spreaders, cooling blocks and thermal bridges.
• Flat faces and sharp corners simplify drilling, tapping, clamping and bolted connections.
• Good ductility and formability; can be cut, drilled, milled, filed and bent.
• Strong resistance to atmospheric corrosion; easy to solder and braze.
• Multiple sizes and lengths available to match your design and reduce scrap.

Typical Properties of Copper C11000 (ETP)

• Copper content: 99.90% minimum (including silver), with a small controlled oxygen content of about 0.02–0.04%.
• Electrical conductivity: 100% IACS minimum in the annealed condition – the international benchmark for electrical-grade copper.
• Thermal conductivity: approximately 391 W/m·K at room temperature.
• Density: approximately 8.89 g/cm³ (0.321 lb/in³).
• Melting point: approximately 1,083 °C (1,981 °F).
• Corrosion resistance: excellent resistance to atmospheric exposure, fresh water and many non-oxidizing chemical environments.
• Related designations: C11000, Alloy 110, ETP (Electrolytic Tough Pitch) copper, Cu-ETP / CW004A, UNS C11000.

Common Applications

• Electrical distribution: busbars, jumpers, bonding links, ground bars, switchgear and panel connections.
• Industrial equipment: welding and resistance-welding components, electrodes, contacts and furnace parts.
• Thermal management: heat sinks, cold plates, heat-spreading blocks and laboratory equipment.
• Machining and prototyping: custom copper blocks, spacers, terminals and precision parts.
• Architectural and decorative work: railings, accents, furniture details and custom metal art.
• Education and R&D: experimental setups, conductivity tests and student projects.

Working with Copper Square Bar

Copper square bar can be cut with a bandsaw, hacksaw or cold saw using fine-tooth blades and cutting lubricant. Drill and tap with sharp tools and clear chips frequently, since pure copper tends to be gummy. Deburr the edges after cutting for a clean fit. For electrical joints, clean the contact faces, use appropriate hardware and apply the correct torque; plating the joint with tin or silver and using joint compound can further improve long-term performance in demanding environments.

Cutting, Handling and Ordering Notes

Dimensions are nominal and listed in inches. As with all drawn and rolled copper products, small dimensional tolerances apply, and the surface of the metal naturally develops a darker oxide patina over time without affecting performance. Wear gloves when handling to keep the surface clean, store the material in a dry place, and keep it separated from steel and other dissimilar metals during storage to avoid surface staining. If you need a quantity, length or size that is not listed, please contact us and we will be glad to help.