Chemical Composition (%)
| Cu | 79.0~81.0 |
|---|---|
| Si | 2.5~4.5 |
| Zn | Balance |
Mechanical & Physical Properties
| Tensile strength | ≥345 MPa (sand cast S / permanent mould R) |
|---|---|
| Yield strength Rp0.2 | ≥180 MPa |
| Elongation | ≥15% |
| Density | 8.32 g/cm³ |
Typical Applications
Grade Overview
ZCuZn16Si4 is a silicon brass with about 16% zinc and 2.5-4.5% silicon, corresponding to UNS C87400. Silicon suppresses dezincification and produces a fine, pressure-tight cast structure, giving good corrosion resistance in water together with tensile strength of at least 345 MPa and elongation of at least 15%. It is a standard choice for valves, pumps and water fittings.
Selecting ZCuZn16Si4
Choose ZCuZn16Si4 for valve bodies, pump bodies, impellers, pipe fittings and flanges exposed to water, where pressure tightness and corrosion resistance matter more than the highest strength. For seawater duty with higher strength, an aluminium brass such as ZCuZn35Al2Mn2Fe1 is stronger; for general structural brass at lower cost, ZCuZn40Mn2 is adequate.
Working with ZCuZn16Si4
Silicon brasses are prone to gas porosity, so degas the melt and use clean, dry charge materials. The alloy casts well in sand and permanent moulds and machines cleanly. Avoid overheating, which increases zinc loss and porosity. No heat treatment is required; pressure test critical castings before machining the sealing faces.
Frequently asked questions about ZCuZn16Si4
What is ZCuZn16Si4 equivalent to?
It corresponds to UNS C87400 silicon brass. EN designations differ; confirm the exact grade on the certificate.
Is silicon brass resistant to dezincification?
Silicon addition greatly reduces dezincification compared with ordinary yellow brasses, which is why the grade is used for water fittings.
Can it be welded?
Brazing and soldering are straightforward; fusion welding is possible but needs care because of zinc fume and porosity. Many parts are cast to shape and machined instead.
Data compiled from current standards; for selection reference only. Ordering is subject to the standard and the mill certificate. Data source: Shenyang Yuheng Metal Manufacturing Co., Ltd. — yuhengmetal.com.
Related cast copper alloy grades
ZCuZn40Mn2 · ZCuZn25Al6Fe3Mn3 · ZCuZn38Mn2Pb2 | All 52 grades in the library