Silicon tombac

Standardized copper-zinc-silicon alloy CuZn16Si4-C with the following composition (Table 1):

The alloy is also called silicon bronze and is also known under the brand name Tombasil. It has outstanding casting properties and good strength properties (Rm: 400 to 530 MPa, Rp0.2: 230 to 370 MPa, A: 5 to 10%, hardness: 100 to 150 HB).

The alloy displays low permeability and good corrosion resistance; it is resistant to dezincification in aggressive media and is used for sand, die and pressure die casting.

This alloy is used in the casting of fittings and casing for salt water pumps are also made from it.

Literature references:
Deutsches Kupferinstitut (DKI), Kupferschlüssel, www.kupferschlü
EN 1982:1998, Kupfer und Kupferlegierungen, Blockmetalle und Gussstücke
Bayerisches Online-Materialinformationssystem,


  • Table 1: Chemical composition of the alloy CuZn16Si4-C according EN 1982:1998