Electrolytic-tough pitch (ETP) copper

Electrolytic-tough pitch (ETP) copper

Electrolytic tough pitch copper, UNS C11000, is pure copper (with a maximum of 0.0355% impurities) refined by the electrolytic refining process. It is the most widely used grade of copper all over the world. ETP has a minimum conductivity rating of 100% IACS and is required to be 99.9% pure. It has 0.02% to 0.04% oxygen content (typical). Electrical wiring is the most important market for the copper industry. This includes structural power wiring, power distribution cable, appliance wire, communications cable, automotive wire and cable, and magnet wire. Roughly half of all copper mined is used for electrical wire and cable conductors. Pure copper has the best electrical and thermal conductivity of any commercial metal. The conductivity of copper is 97% that of silver. Due to its much lower cost and greater abundance, copper has traditionally been the standard material for electricity transmission applications.

According to the Copper Development Association:

“The term ‘tough pitch’ originates from the time when molten copper, after refining, was cast into ingot moulds. During refining, the copper was oxidized to remove impurities and then reduced by hydrogen to give the correct oxygen level. To monitor this process, a small sample was taken, and the solidification surface was observed. If the surface sunk, there was too much oxygen; if it was raised, there was too much hydrogen. If it was level (correct pitch), the oxygen was correct, and the properties good; in other words, ’ tough,’ hence tough pitch. “

Source: https://copperalliance.org

Application of ETP

Electrolytic tough pitch copper plays a critical role in a wide range of applications, including:

1. Electrical wiring: Electrical conductors such as copper wires are used for electrical wiring in buildings, homes, and industrial facilities.
2. Electronics: Electrical conductors are used in a wide range of electronic devices, including televisions, computers, smartphones, and more.
3. Power transmission: Electrical conductors are used in power transmission lines to transmit electricity over long distances from power plants to homes and businesses.
4. Automotive industry: Electrical conductors are used in various automotive applications, including wiring harnesses, spark plugs, and battery cables.
5. Lighting: Electrical conductors are used in lighting applications, including incandescent, fluorescent, and LED lighting.
6. Medical equipment: Electrical conductors are used in a wide range of medical equipment, including ECG machines, X-ray machines, and MRI machines.
7. Aerospace industry: Electrical conductors are used in the aerospace industry for a variety of applications, including wiring, sensors, and communication systems.
8. Renewable energy: Electrical conductors are used in renewable energy systems, including wind turbines and solar panels, to transmit power from the energy source to the electrical grid.

Characteristics of ETP

Some of the key characteristics of pure ETP copper include:

1. High electrical conductivity: ETP copper has a high electrical conductivity, which means that it can efficiently transmit electrical current with low resistance.
2. Ductility: ETP copper is a ductile material, which means that it can be easily drawn into wires and cables without breaking or cracking.
3. Corrosion resistance: ETP copper is resistant to corrosion, which helps to ensure that it can maintain its performance over time.
4. High thermal conductivity: ETP copper also has a high thermal conductivity, which means that it can efficiently transfer heat.
5. Low impurities: ETP copper is a high-purity copper that contains very low levels of impurities, such as oxygen and sulfur, which can negatively affect its electrical properties.
6. Good machinability: ETP copper is relatively easy to machine and can be formed into a variety of shapes and sizes, making it suitable for a range of electrical applications.

Here is a table of 10 most common conductors with their main parameters:

Conductor	Electrical Conductivity (S/m)	Thermal Conductivity (W/m*K)	Melting Point (°C)	Density (g/cm³)
Silver (Ag)	62.6 × 10^6	429	961.8	10.49
Copper (Cu)	58.0 × 10^6	401	1,085	8.96
Gold (Au)	45.5 × 10^6	320	1,064	19.30
Aluminum (Al)	37.7 × 10^6	237	660.3	2.70
Tungsten (W)	18.8 × 10^6	173	3,422	19.25
Nickel (Ni)	14.4 × 10^6	91.7	1,455	8.91
Iron (Fe)	10.0 × 10^6	80.4	1,538	7.87
Zinc (Zn)	16.6 × 10^6	116	419.5	7.13
Brass (CuZn)	15.6 × 10^6	109	900-940	8.4-8.7
Bronze (CuSn)	7.8 × 10^6	61.2	870-1,040	7.5-8.8