1. Material standard and composition
Description of the brand name:
Chinese standard (GB/T 5231-2012): TP1 (phosphorus deoxidized copper, phosphorus content 0.004-0.012%).
International counterpart: C12000 in American Standard ASTM B133, phosphorus content 0.004-0.012%. Oxygen content ≤ 0.01%.
C12000 composition requirements (ASTM B133):
Copper (Cu) Phosphorus (P) Oxygen (O) Total other impurities
≥99.90% 0.004-0.012% ≤0.01% ≤0.1%
2. Physical and mechanical properties
Parameter TP1 (C12000) Typical Value Comparison T2 Pure Copper
Density (g/cm³) 8.94 8.92
Electrical Conductivity (IACS, 20°C) 85-90% 98
Thermal Conductivity (W/(m-K)) 320 380
Tensile strength (soft state, MPa) 200-250 180-220
Elongation (soft state, %) ≥45 ≥35
Hydrogen embrittlement susceptibility Extremely low (phosphorus inhibits Cu₂O generation) Ordinary copper is susceptible to hydrogen embrittlement
3. Core Advantages
Welding and machining properties:
Weldability: phosphorus deoxidation to avoid porosity, suitable for flame welding, argon arc welding (weld strength ≥ 90% of the base material).
Hot and cold molding: soft state elongation ≥ 45%, can be deep drawn into complex parts (such as bellows, heat exchanger fins).
Resistance to corrosion and hydrogen embrittlement:
Resistant to high temperature steam (200°C): oxidation rate 50% lower than T2, suitable for boiler water tubes.
No risk of hydrogen embrittlement in hydrogen environments (e.g. annealing furnaces) (ordinary copper is prone to cracking due to the reaction between Cu₂O and H₂).
Cost & Practicality:
Price is 20-30% lower than oxygen-free copper (TU1), which is suitable for high-volume industrial parts with medium electrical/thermal conductivity needs.
4. Typical application scenarios
Heat exchange system:
Air conditioner copper tube: phosphorus deoxidized copper tube (wall thickness 0.3-0.5 mm) pressure ≥ 3 MPa, chlorine ion corrosion resistance.
Automobile water tank heat sink: no cracks on the surface after molding, thermal conductivity retention rate > 95%.
Construction & Engineering:
Building water supply pipe: resistant to cold/hot water corrosion, with a life span of >30 years (in line with GB/T 18033 standard).
Fire sprinkler system: welded joints pass 1.5 times working pressure water pressure test (no leakage).
Electricity & Energy:
Transformer heat sink: welded into honeycomb structure, heat dissipation efficiency increased by 30%.
Solar collector runners: temperature resistant to 150°C, cycle life >100,000 times.
5. Processing and Handling Guidelines
Molding process:
Cold Rolling: Tensile strength is increased to 350 MPa at 70% under pressure (intermediate annealing is required).
Welding: Recommended TIG welding (argon gas purity ≥99.99%), current density 2-3 A/mm².
Annealing process:
Annealing temperature 500-550°C (hydrogen or nitrogen protection), time 1-2 h, hardness recovery to HV 55-60.
Surface treatment:
Passivation process: nitric acid - chromic acid mixture passivation, surface salt spray resistance time > 72 h (ASTM B117).
Tin plating: electroplated tin layer thickness 5-10 μm, contact resistance <0.02 mΩ.
6. Comparison with similar materials
Parameter TP1 (C12000) T2 pure copper (C11000) TU1 oxygen-free copper (C10100)
Conductivity (IACS) 85-90% 98% 101
Welding performance Excellent Good Poor (special protection required)
Hydrogen embrittlement resistance Excellent Poor Excellent
Cost ($/kg) 6-8 5-7 10-12
Scenarios Welding of pipes/radiators Conventional conductive parts Superconductivity/vacuum devices
7. Technology trends and challenges
Thin-wall trend:
Precision cold rolling technology to achieve ultra-thin strips of 0.1 mm thickness (for flexible heat pipes) with a tolerance of ±0.005 mm.
Composite Tubes:
Copper-aluminum composite tubes (TP1 outer layer + aluminum core): 40% weight reduction, thermal conductivity retention > 90%.
