1. Oxygen-Free Copper (OFC)
Oxygen-free copper is produced under strict oxygen control, with oxygen content generally below 10 ppm. It avoids hydrogen embrittlement at high temperatures and has stable conductivity.
Cu-OF (EN) / C10100 (ASTM) / TU1 (GB)
This is the highest-grade oxygen-free copper with extremely low impurity and oxygen content. Its electrical conductivity can reach more than 100% IACS, and it has excellent plasticity and weldability. It is mainly used in high-performance electronic components, vacuum devices, high-frequency signal transmission materials, superconductor encapsulation and other precision fields that require extremely stable electrical performance.
TU2 (GB) / C10200 (ASTM)
Similar to TU1, but with slightly higher allowable impurities, it is the most commonly used oxygen-free copper in industry. It balances performance and cost, and is widely used in cables, conductors, integrated circuit lead frames and welding materials.
2. Tough Pitch Copper (TPC)
Tough pitch copper is the most productive and widely used pure copper, with oxygen content usually between 100–650 ppm. It has good conductivity and processability, but is prone to hydrogen embrittlement under high-temperature hydrogen atmosphere.
Cu-ETP (EN) / C11000 (ASTM) / T2 (GB)
This is the most representative and commonly used tough pitch copper, with conductivity above 97% IACS. It has moderate cost and excellent comprehensive performance, and is the first choice for electrical and thermal conductive parts. Typical applications include power cables, busbars, motor windings, transformer coils, heat exchangers, plumbing and decorative copper parts.
T1 (GB) / C10300 (ASTM)
High-purity tough pitch copper, with fewer impurities than T2, slightly better conductivity and corrosion resistance, mostly used in high-precision electrical products and electronic connectors.
T3 (GB)
Lower purity than T2, with higher impurity content, lower cost, suitable for general industrial parts with low requirements for conductivity, such as hardware stamping parts, daily necessities and structural parts.
3. Deoxidized Copper
Deoxidated copper is deoxidized by phosphorus, lithium or other elements, with very low oxygen content, good welding performance and no hydrogen embrittlement. Phosphorus-deoxidized copper is the most common.
Cu-DLP (EN) / C12000 (ASTM) / TUP (GB)
Phosphorus-deoxidized copper, residual trace phosphorus improves welding and brazing performance, but slightly reduces electrical conductivity (about 85–95% IACS). It is widely used in water pipes, gas pipes, refrigeration pipes, heat exchangers, HVAC equipment and various welding components.
Cu-DHP (EN) / C12200 (ASTM) / TUMn (GB)
High-phosphorus deoxidized copper, with better weldability, suitable for complex welding structures and pipe fittings requiring high processing performance, and is a standard material for copper plumbing and refrigeration pipelines worldwide.
Core Differences Between Grades
The essential differences among pure copper grades lie in oxygen content, impurity level, deoxidation elements and electrical conductivity:
Oxygen content: OFC has the lowest oxygen content, followed by deoxidized copper, and tough pitch copper has the highest. Oxygen content determines high-temperature stability and hydrogen embrittlement resistance.
Electrical conductivity: OFC > tough pitch copper > phosphorus-deoxidized copper. High-conductivity scenarios prefer oxygen-free or tough pitch copper.
Weldability: Deoxidized copper is the best, especially for high-temperature welding and brazing.
Cost and application: Tough pitch copper T2/C11000 has the best cost-performance ratio and the largest consumption; oxygen-free copper is used in high-end electronics; deoxidized copper is dominant in pipelines and welding parts.
