Weight %. At ~40% Zn the beta phase appears — harder and stiffer cold, but superbly workable hot.
| Element | Symbol | Min % | Max % | Typical % |
|---|---|---|---|---|
| Copper | Cu | 59.0 | 62.0 | 60.5 |
| Zinc | Zn | Balance | ~39.5 | |
| Lead (max) ✓ | Pb | — | 0.10 | ≤0.05 |
| Iron | Fe | — | 0.30 | 0.05 |
| Property | Condition | Value | Unit |
|---|---|---|---|
| Tensile Strength (Rm) | annealed | 370–430 | MPa |
| Tensile Strength (Rm) | half-hard | 430–520 | MPa |
| Proof Stress (Rp0.2) | annealed | ≥140 | MPa |
| Elongation (A) | annealed | ≥30 | % |
| Hardness | annealed | 85–105 | HB |
| Machinability | vs C36000 = 100 | ~52% | — |
| Density | — | 8.39 | g/cm³ |
| Melting Range | solidus–liquidus | 895–905 | °C |
| Standard | Designation |
|---|---|
| EN (Europe) | CuZn40 / CW509L |
| ASTM (USA) | C28000 (Muntz Metal) |
| BS (UK legacy) | CZ109 |
| DIN (Germany) | CuZn40 / Ms60 |
| JIS (Japan) | C2801 |
CuZn40 (CW509L) is a 60/40 copper-zinc brass with an alpha-beta duplex structure. The beta phase makes it excellent for hot working — extrusion, hot rolling and forging — which is why it is used for architectural extrusions, condenser tube plates and marine hardware.
Yes — CuZn40 is lead-free by composition and RoHS compliant without exemptions.
They are opposites: CuZn37's all-alpha structure excels at cold forming, while CuZn40's duplex structure prefers hot working and is harder and stiffer cold. Pick CuZn37 for deep drawing at room temperature; pick CuZn40 for hot-extruded or hot-rolled shapes (machinability about 52%).
Rod and profiles are specified in EN 12167 (designation CW509L). The traditional US equivalent is C28000 Muntz Metal, former UK designation CZ109. Brassland supplies EN 10204 Type 3.1 mill certificates with every lot.
Hot-worked and machined to your drawing. ISO 9001:2015. Quote within 24 hours.
Request a QuoteComposition ranges, mechanical properties, machinability ratings and regulatory data on this page are cross-referenced against the publishers below. Tolerances and minimum values are taken from the relevant published standard at the time of writing — for procurement specification, always reference the current published edition.
Last reviewed: June 2026. EN/ISO/ASTM standards are updated periodically. This datasheet reflects the editions listed; for safety-critical or contract-critical applications, always verify against the current published edition of the standard. For project-specific deviations or supplier-specific composition windows, request a Type 3.1 mill certificate (EN 10204) with your order.