Brass vs Copper: Properties, Cost & Applications Compared
Brass and copper are closely related metals — brass is actually a copper alloy — but their properties, costs, and applications differ significantly. Choosing the wrong material can lead to premature failure or unnecessary expense. This guide helps you understand when to specify brass vs copper for your project.
1. What Is the Difference?
- Copper (Cu): A pure elemental metal (99.9%+ Cu). Known for excellent electrical and thermal conductivity, distinctive reddish color, and natural antimicrobial properties.
- Brass: An alloy of copper + zinc (typically 55–95% Cu, 5–45% Zn), often with small additions of lead, tin, or aluminum. Brass properties vary significantly with zinc content.
2. Mechanical Properties Comparison
| Property | Pure Copper (C11000) | Brass (C36000) | Naval Brass (C46400) |
|---|---|---|---|
| Tensile Strength | 210–400 MPa | 310–520 MPa | 415–550 MPa |
| Yield Strength | 69–330 MPa | 170–415 MPa | 170–380 MPa |
| Hardness (HB) | 40–110 | 70–105 | 80–100 |
| Elongation | 15–50% | 10–35% | 25–40% |
Key insight: Brass is stronger and harder than pure copper, making it better for machined parts. Copper is more ductile, making it better for forming and drawing into wire or tube.
3. Corrosion Resistance
- Copper: Excellent resistance to fresh water, seawater, and atmospheric corrosion. Develops protective green patina (verdigris) over time. Resists stress corrosion cracking.
- Brass: Good general corrosion resistance, but susceptible to dezincification in certain water conditions (high chloride, low pH). Naval brass (with tin addition) solves this problem.
4. Machinability
This is where brass significantly outperforms copper:
- Free-machining brass (C36000): Machinability rating of 100% — the benchmark against which all other metals are measured
- Copper: Machinability rating of only 20% — gummy, difficult to machine, poor chip breaking
For CNC-machined parts, brass is almost always the better choice.
5. Electrical & Thermal Conductivity
- Copper: IACS conductivity = 100% (the standard). Used for electrical wiring, busbars, and heat exchangers.
- Brass: IACS conductivity = 15–28% (much lower due to zinc alloying). Not suitable for electrical applications.
6. Cost Comparison
| Material | Approx. Price (USD/kg) | Relative Cost |
|---|---|---|
| Copper (C11000) | $8–10/kg | $$ |
| Brass (C26000) | $6–8/kg | $ |
| Free-machining Brass (C36000) | $7–9/kg | $$ |
| Naval Brass (C46400) | $10–13/kg | $$$ |
Standard brass is generally 20–30% cheaper than pure copper due to the zinc content (zinc is significantly less expensive than copper).
7. When to Use Each
Choose Copper when:
- Electrical conductivity is required (wiring, busbars, connectors)
- Maximum thermal conductivity needed (heat exchangers, cookware)
- Antimicrobial surfaces for healthcare or food processing
- Architectural roofing and cladding (patina aesthetic)
Choose Brass when:
- Precision machined parts (valves, fittings, gears)
- Decorative hardware (door handles, fixtures)
- Plumbing fittings and valves
- Musical instruments
- Marine hardware (naval brass specifically)
Conclusion
Brass and copper each have distinct advantages — brass wins on machinability, strength, and cost; copper dominates in conductivity and formability. CoreMetal Steel supplies both copper and brass in sheets, tubes, bars, and coils. Contact us for competitive pricing on your next project.