In casting process our enterprise uses the next types of bronze:
Tin bronze according to GOST 613-79
Tin - free bronze according to GOST 493-79
Cast tin bronzes according to GOST 613-79 have different mechanical properties depending on chemical content of bronze itself.
According to the agreement with the customer our enterprise has the capability to cast the bronze blanks of parts with different chemical composition and in accordance with different mechanical properties of the bronze. The most demanded grade of tin bronze is CuSn5Zn5Pb5, it means that it contains about 5% of tin, 5% of zinc, 5% of lead and the rest is copper. Depending on the percentage of tin, zinc, lead and other additives the mechanical properties of the bronze are changed.
In bronze of the grade CuSn5Zn5Pb5 the hardness according to Brinell NV is 588 MPa either 60 kgf/mm2, tensile strength is 176, 2 MPa or 18 kgf/mm2, elongation per unit length after rupture 4-6 %.
For example, in bronze of CuSn10Pb10 grade the hardness according to Brinell NV is 735 MPa either 78 kgf/mm2. This bronze grade contains 10% of tin, 10% of lead, the rest is copper.
Cast Tin-free bronzes according to GOST 493-79 also have different mechanical performance depending on chemical content of bronze.At will of our customers it is possibly, i.e. to increase substantially the hardness of tin-free bronze, introducing into its composition a number of the additional chemical elements.
The most demanded tin-free bronze grade is CuAl9F4.
It contains 10% of aluminium, 4% of iron; the rest of it is copper.
The hardness of this grade of bronze according to Brinell NV is 980 MPa or 100 kgf/mm2. If we introduce nickel into the composition of this bronze, then the hardness of alloy can be raised to 2450 MPa or 250 kgf/mm2. Together with nickel it is possible to introduce other elements, on the basis of the technical demand of our customers. In the process of foundry production, the specialists of our plant use clean initial materials for manufacturing the bronze castings. Therefore there is a possibility of obtaining the grades of bronze in accordance with the wishes of our clients.