1. Chemical Composition of C51900 (UNS Designation)
2. Hardness of C51900
Hardness values are measured on as-supplied material (no additional heat treatment). For example, annealed C51900 (O temper) is soft enough for bending/stamping, while spring-tempered (H08) is used for high-load components like springs or fasteners.
Hardness can be increased by further cold working (e.g., rolling, drawing) but may reduce ductility. Conversely, annealing after cold working will soften the alloy and restore ductility.
Testing methods: Brinell hardness (HB) is most common for bulk material; Rockwell B (HRB) for thinner sheets/strips; Vickers (HV) for precise microhardness measurements.
3. Advantages of C51900
① Excellent Mechanical Properties
Balanced Strength and Ductility: Even in cold-worked tempers (e.g., full-hard), C51900 retains good ductility, allowing for forming, bending, and machining without cracking.
High Fatigue Resistance: Superior resistance to repeated stress (e.g., in springs, valves, or connectors), making it suitable for high-cycle applications.
Good Machinability: While harder than pure copper, C51900 can be easily machined (drilled, tapped, milled) with standard tools, especially in annealed or half-hard tempers.
② Outstanding Corrosion Resistance
Resists corrosion in freshwater, seawater, and mild chemicals (e.g., acids, alkalis, and organic solvents).
Excellent resistance to dezincification, stress corrosion cracking (SCC), and pitting-critical for marine, plumbing, and industrial environments.
Unaffected by atmospheric corrosion (humidity, rain, pollution), ensuring long-term durability in outdoor applications.
③ Superior Electrical and Thermal Conductivity
Electrical conductivity: ~20–25% IACS (International Annealed Copper Standard), making it ideal for electrical connectors, terminals, and switches.
Thermal conductivity: ~50–60 W/(m·K) (at 20°C), suitable for heat exchangers, heat sinks, and thermal management components.
④ Excellent Wear and Friction Properties
High wear resistance and low coefficient of friction, even under dry or lubricated conditions.
Suitable for bearing applications, bushings, gears, and sliding components (e.g., in automotive or industrial machinery) where abrasion resistance is critical.
⑤ Versatile Formability and Fabrication
Can be cold-worked (rolled, drawn, stamped, bent) into complex shapes, even in half-hard or full-hard tempers.
Weldable via brazing, soldering, or gas welding (arc welding is not recommended due to potential grain growth and brittleness).
Castable into near-net-shape components (e.g., via sand casting or die casting) for cost-effective production of large parts.
⑥ Biocompatibility and Safety
Low lead content (≤0.05 wt%) and non-toxic nature make it suitable for food contact applications (e.g., valves, fittings) and medical devices (e.g., surgical instruments, implants-when certified to biocompatibility standards like ISO 10993).
⑦ Wide Temperature Range Suitability
Operates reliably from -200°C to 200°C (short-term exposure up to 300°C). Retains mechanical properties and corrosion resistance in both low-temperature (e.g., aerospace) and moderate-temperature (e.g., industrial) environments.
