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Brass vs Copper: Which Metal for Fittings, Valves and Electrical?
Brass and copper are both red metals, but they are engineered for different jobs. Copper is pure, soft and conductive — the default for electrical and thermal applications. Brass is a copper-zinc alloy, mai puternic, harder and easier to machine — the default for fittings, valves and hardware. This guide explains when to choose which.
The Core Difference
Cupru (C11000 ETP) is 99.9 % pure copper. It conducts electricity at 101 % IACS and heat at 391 W/m·K, but it is soft (220 MPa la tracțiune) and dents easily. Alamă (C26000, C28000) adaugă 30 – 40 % zinc, raising tensile strength to 330 – 450 MPa and making it machinable, but conductivity drops to 25 – 28 % IACS. În scurt: copper carries current and heat, brass carries load and threads. Vezi noastre C11000 copper plate şi C12200 copper tube.
| Proprietate | Cupru (C11000) | Alamă (C36000) |
|---|---|---|
| Composition | 99.9 % Cu | 60 % Cu, 39 % Zn, 1 % Pb |
| Electrical conductivity | 101 % IACS | 26 % IACS |
| Rezistență la tracțiune | 220 – 360 MPa | 330 – 450 MPa |
| Prelucrabilitate | Sărac (gummy) | Excelent (free-cutting) |
| Rezistenta la coroziune | Excelent (atmospheric) | Bun (dezincification risk) |
| Utilizare tipică | Busbars, tub, wire | Fitinguri, supape, hardware |
When to Use Which
Use copper for electrical busbars, înfăşurările transformatorului, grounding, water supply tube, refrigeration lines and heat exchangers. If the part carries current or heat, choose copper. Use brass for threaded fittings, valve bodies, pump components, angrenaje, bushings and decorative hardware. If the part needs to be machined to tight tolerances, hold a thread, or resist mechanical wear, choose brass. For plumbing, the tube is copper (C12200 DHP) but the fittings and valves are brass — that is the standard combination because the brass fitting is threaded and the copper tube is brazed onto it.
Common Mistakes
The most common error is using brass for electrical conductors because it looks “stronger.” Brass at 26 % conductivity runs hot and wastes energy — always use pure copper for current-carrying parts. The reverse error is using pure copper for valve bodies because it is “more corrosion resistant.” Pure copper is too soft to hold threads under pressure, and it will deform over time. The other risk with brass is dezincification: in aggressive water, the zinc leaches out, leaving porous copper that crumbles. For potable water, specify dezincification-resistant brass (DZR, C352) or use bronze instead.
