What is C21000 brass?
C21000 Brass Strip offers excellent corrosion resistance, making it resistant to seawater erosion and oxidation, which has led to its widespread use in the marine industry. Additionally, this material possesses outstanding electrical and thermal conductivity, making it highly suitable for applications such as marine cables, electrical equipment, and heat exchangers. Furthermore, C21000 brass strip exhibits excellent workability-it can be processed through cold rolling, hot rolling, and other techniques to produce products in various shapes and specifications, meeting diverse industrial requirements.
The application prospects of C21000 Brass Strip in the marine industry are closely linked to market demand. As marine engineering projects continue to advance domestically and internationally, the requirements for materials are becoming increasingly stringent. Due to its high corrosion resistance, excellent workability, and superior electrical conductivity, C21000 brass strip has become an indispensable material in the marine sector, with growing market demand.
Mechanical Properties
Tensile strength, σb (MPa): ≥205
Elongation, δ10 (%): ≥35
Elongation, δ5 (%): ≥42
Heat Treatment Specifications
Hot working temperature: 775 – 850 °C
Annealing temperature: 540 – 600 °C
Key Selection Criteria & Precautions
Differentiation from Pure Copper:
C21000 is a brass (copper‑zinc alloy). While pure copper offers superior electrical and thermal conductivity, C21000 provides a more cost‑effective solution with higher strength. Select according to specific application needs.
Corrosion Resistance:
It performs well in atmospheric, freshwater, and slow‑moving (non‑high‑velocity) seawater environments, where it tends to form a dense protective oxide film. Avoid prolonged use in ammonia‑containing or strongly acidic media to prevent stress corrosion cracking.
Environmental & Regulatory Compliance:
With its low lead content (≤0.05%), C21000 meets potable water and environmental standards for electronics, making it suitable for food‑contact components and electronic parts.
Storage & Maintenance:
Store in moisture‑proof packaging in environments with relative humidity below 60%. Keep away from sulfur‑ and chlorine‑containing atmospheres to prevent surface oxidation and discoloration.
C21000 vs. C11000 (Electrolytic Tough Pitch Copper)
| Property | C21000 (Gilding Metal) | C11000 (ETP Copper) | Key Difference |
|---|---|---|---|
| Composition | 95% Cu, 5% Zn (Alloy) | 99.9% Cu (Pure metal) | C11000 is essentially pure copper. |
| Color | Red-gold | Classic copper red | C11000 has the distinctive reddish color of pure copper. |
| Mechanical | Higher strength than pure copper, excellent ductility | Lower strength, very high ductility and malleability | C21000 is stronger; C11000 is softer and more malleable. |
| Conductivity | ~80-85% IACS | ~101% IACS (Standard) | C11000 has significantly superior electrical/thermal conductivity. |
| Corrosion Resistance | Good | Excellent | Pure copper (C11000) generally has better overall corrosion resistance. |
| Primary Uses | Decorative, electrical connectors, jewelry | Electrical wire/ busbars, heat exchangers, roofing | C11000 for pure conductivity; C21000 for strength + color. |
| Cost | Lower than pure copper | Higher | C21000 is often a cost-effective alternative when conductivity requirements allow. |
How to Choose:
Choose C11000 when the application is primarily electrical or thermal (busbars, windings, heat exchangers) and requires maximum conductivity, or when pure copper's corrosion resistance is critical.
Choose C21000 when you need a balance of good (but not maximum) conductivity, higher strength than pure copper, and a durable, attractive gold-like appearance for decorative or structural-electrical parts.
FAQ
| Q: Where can I buy C21000 brass sheet or strip? A: C21000 products are supplied by specialized metal distributors, mills, and online metal suppliers. Ensure the supplier provides certified Mill Test Reports (MTR) for quality assurance. |
| Q: Does C21000 contain lead? A: Standard C21000 is typically lead-free. However, always verify with the supplier's material certification to ensure compliance with regulations like RoHS or NSF for specific applications. |
| Q: What tempers or forms is C21000 available in? A: C21000 is commonly supplied in annealed (soft), half-hard, and hard tempers. Available forms include sheet, strip, foil, wire, tube, and occasionally rod. |
| Q: Can C21000 be polished or plated? A: Yes, C21000 takes well to mechanical polishing, buffing, and electroplating (e.g., nickel, gold, or chrome) for enhanced appearance and durability. |
| Q: Is C21000 suitable for marine applications? A: C21000 is not ideal for direct seawater exposure due to potential dezincification. For marine environments, alloys like C46400 (naval brass) or copper-nickel alloys are preferred. |
| Q: What are the thermal conductivity and electrical conductivity of C21000? A: C21000 has about 80–85% IACS electrical conductivity and thermal conductivity around 100–120 W/(m·K), making it suitable for certain electrical and heat exchange applications. |
| Q: How does C21000 compare to pure copper in conductivity? A: C21000 has lower electrical and thermal conductivity than pure copper (C11000, ~101% IACS) due to its zinc content, but it offers better strength and formability. |
| Q: What standards cover C21000 brass? A: C21000 is covered by ASTM B36 (sheet/plate), ASTM B134 (wire), ASTM B135 (tube), SAE J461, and other relevant ASTM/UNS specifications. |
Our factory
Our supply scope covers a comprehensive range of high-performance copper and copper alloy products tailored to diverse industrial applications. We provide precision-engineered copper tubes for HVAC and refrigeration systems, sheets and plates for architectural cladding and electrical components, rods and bars for machining and fabrication, wires for conductive and mechanical purposes, as well as strips and foils for electronic and automotive industries. All products are available in various alloys - including pure copper, brass, bronze, phosphor bronze, copper-nickel, and specialty alloys - and can be supplied in standard sizes or customized dimensions, tempers, and finishes to meet your exact specifications.
