Lead-Free Brass is a copper–zinc alloy engineered without, or with extremely low, lead content to meet modern environmental and health regulations.
Instead of lead, alternative elements such as silicon or bismuth are used to maintain strength, machinability, and corrosion resistance, making lead-free brass suitable for potable water, food-grade, medical, and regulated applications.
Compliance: RoHS, REACH, NSF/ANSI 61, WRAS
Typical Chemical Composition
Silicon-Based Lead-Free Brass (C69300)
| Element | Typical % | Metallurgical Role |
|---|---|---|
| Copper (Cu) | 73 – 77 | Corrosion resistance, ductility |
| Zinc (Zn) | Balance | Strength |
| Silicon (Si) | 2.5 – 4.0 | Strength, machinability |
| Phosphorus (P) | Trace | Deoxidation |
| Lead (Pb) | ≤ 0.25% | Regulatory limit |
Bismuth-Based Lead-Free Brass
| Element | Typical % |
|---|---|
| Copper (Cu) | 60 – 65 |
| Zinc (Zn) | Balance |
| Bismuth (Bi) | 1 – 3 |
| Lead (Pb) | ≤ 0.25% |
Physical Properties
| Property | Typical Range |
|---|---|
| Density | 8.1 – 8.5 g/cm³ |
| Melting Range | 880 – 1000 °C |
| Electrical Conductivity | 15 – 25% IACS |
| Thermal Conductivity | 90 – 120 W/m·K |
| Thermal Expansion | 18 – 20 µm/m·°C |
| Magnetic Property | Non-magnetic |
| Appearance | Yellow to slightly reddish gold |
Mechanical Properties
| Property | Typical Range |
|---|---|
| Tensile Strength | 350 – 650 MPa |
| Yield Strength | 200 – 500 MPa |
| Elongation | 8 – 40% |
| Hardness | 90 – 200 HB |
| Modulus of Elasticity | ~100 GPa |
| Machinability | 60 – 85% (vs C36000 = 100%) |
Metallurgical Behavior
Lead-free brass typically has an α + β brass matrix. Silicon forms hard κ (kappa) intermetallic phases, while bismuth appears as soft, discrete particles.
Strengthening occurs through solid-solution strengthening, intermetallic strengthening (Si-brass), and cold working. Lead-free brass is not heat-treat hardenable.
Corrosion Resistance
Excellent resistance to potable water corrosion
High resistance to dezincification (DZR)
Good stress corrosion cracking resistance
Meets DZR brass standards
Key Characteristics
✔ Safe for drinking water
✔ Environmentally compliant
✔ High strength and wear resistance
✔ Non-magnetic and non-sparking
✔ Long service life
Note: Machinability is slightly lower than leaded brass, but performance is optimized with proper tooling.
Processing Behavior
| Process | Performance |
|---|---|
| Hot extrusion | Excellent |
| Cold drawing | Excellent |
| CNC machining | Good |
| Forging | Good |
| Casting | Good |
| Welding | Fair |
| Brazing / Soldering | Excellent |
| Plating | Excellent |
Available Forms
Rods (round, hex, square)
Sheets and plates
Pipes and tubes
Forged blanks
Precision extrusions
Custom machined components
Applications
Potable water plumbing and valves
Food and beverage processing equipment
Medical and sanitary fixtures
Electrical terminals and connectors
Automotive and industrial fluid fittings
Advantages
✔ Global regulatory compliance
✔ Safe for human contact
✔ Excellent corrosion resistance
✔ Sustainable and recyclable
✔ Future-proof material choice
Why Choose Lead-Free Brass?
Lead-free brass is the correct choice when human health, potable water safety, regulatory compliance, and long-term corrosion resistance are mandatory.
Lead-Free vs Leaded Brass
| Property | Lead-Free Brass | Leaded Brass |
|---|---|---|
| Health Safety | Excellent | Poor |
| Machinability | Good | Excellent |
| Strength | Higher | Moderate |
| Corrosion Resistance | Excellent | Moderate |
| Regulatory Acceptance | Global | Restricted |