3/8″ .375″ Copper Round Bar (Alloy 110 – ETP)

Copper Round Bar – Alloy 110 (C11000 / ETP)

Our copper round bar is manufactured from Alloy 110, also known as C11000 or Electrolytic Tough Pitch (ETP) copper, the most widely used grade of commercially pure copper in the world. With a minimum copper content of 99.9% and a conductivity rating of 100% IACS, this solid round bar delivers outstanding electrical and thermal performance together with excellent ductility, making it a dependable choice for both industrial buyers and small workshops.

The bar has a smooth, uniform round profile and a bright reddish-gold finish. It can be cut, drilled, turned, bent, brazed, soldered and welded with the appropriate techniques, so it adapts easily to a wide range of manufacturing and repair tasks. Each listing in this category corresponds to a specific diameter and cut length, so you can order exactly what your project requires and minimize waste.

Key Features and Benefits

• Solid round section in 99.9% pure copper (C11000 / ETP) for consistent, predictable performance.
• Very high electrical conductivity (100% IACS minimum), ideal for current-carrying applications.
• Excellent thermal conductivity for heat-transfer and heat-dissipation components.
• Outstanding formability: can be bent, forged, swaged and drawn without cracking.
• Good corrosion resistance in indoor, outdoor and many industrial environments.
• Readily joined by soldering and brazing; can be welded with suitable processes.
• Available in multiple diameters and cut lengths to suit different budgets and applications.

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 and power: grounding and earthing electrodes, connectors, terminals, switchgear components, busbar connections and transformer parts.
• Machining: turned and milled parts such as contacts, electrodes, welding tips, fittings and custom components.
• Heat transfer: heat sinks, cooling blocks, induction and welding equipment, and thermal conductors.
• Fabrication and repair: structural and decorative metalwork, plumbing components, hardware and prototype parts.
• Arts, crafts and education: blacksmithing, jewelry and sculpture, hobby projects and laboratory experiments.
• Industrial and marine: general maintenance, tooling and equipment where corrosion resistance and conductivity are valued.

Working with Copper Round Bar

Pure copper is soft and gummy compared with steel or brass, so use sharp tooling, generous lubrication and moderate cutting speeds when machining. Copper work-hardens as it is formed, so for heavy bending or forging it can be annealed by heating to a dull red and quenching or air-cooling to restore softness. When soldering or brazing, thoroughly clean the surface and use a suitable flux. For high-current electrical connections, ensure the contact surfaces are clean, flat and properly torqued to maintain low resistance.

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.