If you are trying to sort out the copper alloy families and only remember one thing, make it this: the name tells you what the second ingredient is — pure copper is for conductivity, brass adds zinc for machinability and looks, and bronze adds tin for bearing and spring duty.
The copper family is not one material; it is a group of alloys that behave differently enough that a drawing that just says "copper" or "brass" is usually unbuildable. The grade number is what makes it specific, and the number system — the UNS C-series in the US, the T/H/Q series in China — is what you write on the order to remove the ambiguity.
The families in one table
| Family | Typical grades | Second element | What it is for |
|---|---|---|---|
| Pure copper | C11000, C10100, C10200 (T1, T2, T3) | — (99.9% Cu min) | Conductivity, busbar, transformer, cable |
| Brass | C260, C270, C360 (H62, H65, H59) | Zinc | Machining, fittings, decoration |
| Tin bronze | C51000, C52100 | Tin | Bearings, springs, bushings |
| Aluminum bronze | C61400, C63000 | Aluminum | Marine, valve seats, high strength |
| Beryllium copper | C17200 | Beryllium | Springs, connectors, non-sparking tools |
| Cupronickel | C71500 | Nickel | Marine condensers, seawater service |
What each one is actually bought for
- Pure copper (C11000 et al.) is bought for conductivity — busbar, transformer winding, cable, heat-sink base. It is soft, easy to form, and the purity is what carries the current. The 61% IACS-aluminum comparison lives here.
- Brass (C260 / C360) is bought for machinability and appearance. C360 free-cutting brass is the reference standard for machinability; the lead addition breaks the chip. It is the economical answer for high-volume turned parts.
- Tin bronze (C51000 / C52100) is bought for bearing and spring duty. The tin gives it low friction against steel and a good fatigue life. Phosphor bronze is the go-to for electrical springs and contacts.
- Aluminum bronze and cupronickel are the marine and corrosive-service answers, but here the honest comparison is that stainless steel usually wins the same argument at a similar or lower cost, with a bigger supply base.
How the grade systems line up
The US UNS C-series and the Chinese grades are two names for the same alloys, and the correspondence is what lets an order cross a border without a mistake. C11000 is T2; C260 is H65 or H70; C360 is H59 or HPb59-1. When a drawing names one system and the mill quotes the other, the order should state both, plus the standard — ASTM B152 for copper sheet, ASTM B16 for brass bar — so the certificate is checkable against a named specification rather than a translated memory.
Supplying stainless steel and aluminum, not copper. At Hongming Metal, copper alloys are a reference line we write about, not a range we sell. If your application is moving toward corrosion resistance or structural duty — which is where copper alloys start to lose on cost — the stainless steel and aluminum ranges are what we actually ship. Start with the stainless steel fittings and flanges range.