Electrolytic Tough Pitch (ETP) Copper

Electrolytic Tough Pitch Copper (ETP Copper), designated as C11000, is the most widely used grade of commercial copper. It contains approximately 99.9% pure copper with a small controlled oxygen content, providing exceptional electrical and thermal conductivity.

ETP copper is refined through electrolytic processes to achieve high purity and is the preferred material for electrical, power transmission, and high-conductivity applications across global industries.

Chemical Composition

ElementTypical %
Copper (Cu)99.90 – 99.95
Oxygen (O)0.02 – 0.04
Silver (Ag)~0.02 (trace)
Other Impurities< 0.01 total

Note:
Oxygen exists as finely dispersed Cu₂O (cuprous oxide) particles at grain boundaries, which enhances conductivity but limits use in hydrogen-rich environments.

Key Physical Properties

PropertyTypical Value
Density8.94 g/cm³
Melting Point1083°C
Electrical Conductivity100 – 101% IACS
Electrical Resistivity~1.68 μΩ·cm
Thermal Conductivity~390 – 401 W/m·K
Coefficient of Thermal Expansion16.5 × 10⁻⁶ /°C
Magnetic BehaviorNon-magnetic
Crystal StructureFCC

Key Mechanical Properties

Property Annealed (Soft) Half Hard Hard
Tensile Strength 200 – 220 MPa 250 – 300 MPa 350 – 420 MPa
Yield Strength ~70 MPa ~200 MPa ~350 MPa
Elongation 35 – 45% 10 – 20% 2 – 5%
Hardness (HV) 40 – 55 70 – 95 100 – 120

Strengthening & Metallurgical Behavior

✔ FCC crystal structure ensures excellent ductility
✔ Strength increases through cold working (strain hardening)
✔ No precipitation or age hardening
✔ Annealing at 200–300°C restores ductility and conductivity
✔ Grain size controlled through thermal treatment

Key Characteristics of ETP Copper

✔ Exceptional electrical conductivity
✔ Excellent thermal conductivity
✔ Very good formability (rolling, drawing, bending)
✔ Excellent solderability and brazability
✔ Non-magnetic
✔ Cost-effective compared to oxygen-free grades
✔ Highly recyclable

Limitation:
ETP copper is not suitable for hydrogen-rich or reducing atmospheres at high temperature due to hydrogen embrittlement caused by Cu₂O.

Refining & Processing Properties

✔ Electrolytic refining for high purity
✔ Oxygen controlled during casting
✔ Excellent hot and cold workability
✔ High drawability into fine wires
✔ Easily rolled into sheets, strips, and foils
✔ Compatible with extrusion and forging

Available Forms

Copper rods (CCR rods)
Copper wires and cables
Copper strips and foils
Copper sheets and plates
Copper bars and busbars
Tubes and pipes
Custom profiles and extrusions

Applications of ETP Copper

Electrical & Power
Wires and cables
Busbars and conductors
Transformers and generators
Switchgear components

Electronics
PCB tracks
Connectors and terminals
Motor windings
Inductors and coils

Industrial & Infrastructure
Heat exchangers
Welding electrodes
Earthing systems
Power distribution and grounding

Advantages of ETP Copper

✔ Industry-leading conductivity
✔ Excellent ductility and workability
✔ Reliable electrical performance
✔ Economical versus oxygen-free copper
✔ Strong global availability
✔ Easy fabrication and joining

Why Choose ETP Copper?

Choose Electrolytic Tough Pitch Copper when you need maximum electrical efficiency, high-volume production capability, cost-effective conductivity, easy fabrication, and proven reliability across industries.

Engineering Recommendation:
ETP copper is the default material for electrical and power applications where hydrogen exposure or extreme vacuum conditions are not present.

Sustainability & Recycling

✔ 100% recyclable without property loss
✔ Lower energy demand compared to primary copper
✔ Widely reused in electrical scrap recovery