C12000 Oxygen Free Copper Details
C12000 oxygen-free copper is a high-performance copper alloy material, due to its excellent electrical conductivity, thermal conductivity and processing performance, has a wide range of applications in electronics, electrical, welding and other fields. The following will be from the material characteristics, production process, application areas, market status and development trends, etc., a comprehensive introduction to this material.
First, material properties and chemical composition
C12000 oxygen-free copper belongs to the phosphorus deoxygenation copper series, its core feature is the extremely low oxygen content (usually ≤ 0.003%). By adding trace phosphorus (0.004%-0.012%) as a deoxidizer, the material significantly improves weldability and resistance to hydrogen embrittlement while maintaining high purity copper performance. Compared with ordinary pure copper, its typical properties are shown as:
1. **Electrical and thermal conductivity**: electrical conductivity up to 98% IACS or more, thermal conductivity of about 380W/(m-K), close to the theoretical value of pure copper;
2. Mechanical properties: annealed state tensile strength ≥ 200MPa, elongation ≥ 35%, cold working strength can be increased to more than 400MPa;
3. Process performance: excellent hot and cold processing molding properties, can be drawn into the diameter of 0.01mm below the ultra-fine wire material;
4. Special stability: in the reducing atmosphere will not occur "hydrogen disease" phenomenon, high temperature environment, oxidation resistance is outstanding.
Second, the key points of the production process
The production of C12000 adopts the process chain of "vacuum melting - continuous casting and rolling", and the core technology links include:
1. raw material selection: copper cathode purity ≥ 99.99%, phosphorus additives need to be specially purified. 2. vacuum melting: in 10 minutes, the cathode is melted in a vacuum melting process;
2. vacuum melting: melting in 10^-3Pa vacuum environment, effectively controlling gas inclusions. 3. deoxidizing process: adopting the "Deoxidizing Process", which is the most effective way of deoxidizing copper cathodes;
3. deoxidizing process: using "phosphorus-copper intermediate alloy" to ensure the uniform distribution of phosphorus elements;
4. Continuous casting control: the application of electromagnetic stirring technology makes the grain size of cast billet reach ASTM 6 or above;
5. precision rolling: multi-channel rolling process makes the finished product thickness tolerance control in ± 0.001mm.
A leading enterprise adopts "horizontal continuous casting - planetary rolling" innovative process, so that 8mm billet rolled into 0.1mm strip, processing efficiency by 40%, reduce energy consumption by 25%.
Third, the main application areas
1. electronic packaging: used as LED bracket, IC lead frame, a model of TO-220 packaging device using C12000, thermal resistance reduced by 18%;
2. power transmission: high-voltage vacuum switch contact materials, in the 40.5kV grade switch in the electric life of more than 100,000 times;
3. welding field: as melting electrode gas shielded welding (MIG welding) wire material, especially suitable for stainless steel dissimilar metal welding;
4. special cables: submarine fiber optic cable armor layer materials, in the 8,000-meter deep sea environment and still maintain stable performance;
5. new energy equipment: fuel cell bipolar plate coating substrate, so that the output power density of a single cell increased to 1.2W/cm².
According to industry statistics, in 2024, China's C12000 in the semiconductor field of the amount of year-on-year growth of 23%, of which the consumption of 12-inch wafer manufacturing equipment accounted for 37%.
Fourth, the current market situation analysis
1. Supply and demand pattern: the global annual production capacity of about 250,000 tons, mainly concentrated in Nippon Mining & Metals, Wieland, Chalco Luo Copper and other enterprises. Domestic high-end products are still dependent on imports, and the unit price of imports is 40-60% higher than that of domestic products;
2. price trend: 2024 Q4 spot price maintained at 78-85 yuan / kg, significantly affected by copper price fluctuations;
3. technical barriers: ultra-fine wire (diameter <0.03mm) of the filament breakage rate control is still the industry's difficulties, Japanese companies can do ≤ 0.5 times / million meters;
4. Alternative materials: copper-silver alloy (C15000) in some high-frequency scenarios to form competition, but the cost is higher than 30%.
V. Future Development Trends
1. microstructure control: through rare earth microalloying (such as adding 0.03% Ce) can make the recrystallization temperature by 50 ℃;
2. Composite development: copper - graphene composite materials R & D breakthroughs, laboratory samples conductivity increased by 12%;
3. Green manufacturing: direct electrolytic refining technology for copper scrap can reduce carbon emissions by 35%;
4. application expansion: in the quantum computer superconducting magnets, space radiation protection layer and other emerging fields began to trial.
The latest research of a scientific research institution shows that the fatigue life of C12000 components molded by selective laser melting (SLM) 3D printing reaches 92% of the traditional process products, which opens up a new path for the manufacture of complex structural components.
