Extract from TU for forgings BrNHK(f)
TU "Bronze forgings BrNHK(f)"
TU 1846-004-80569151-2013
1.1.8 The hardness and electrical conductivity of heat-treated forgings must be at least 200 HB and 24 MS/m, respectively.
1.2 Requirements for materials
1.2.1 Forgings are made of BrNHK(f) bronze. The chemical composition of the alloy in terms of main components and impurities must meet the requirements specified in Table 4.
Table 4 Chemical composition of bronze BrNHK(f)
| main components, % | ||||||||
| Copper (Cu) | Nickel (Ni) | Chromium (Cr) | Silicon (Si) | |||||
| Warp | 2.4-2.8 | 0.5-1.0 | 0.5-0.9 | |||||
| maximum impurity content, % | ||||||||
| Iron (Fe) | Phosphorus (P) | Lead (Pb) | Tin (Sn) | Zinc (Zn) | Total | |||
| 0.10 | 0.03 | 0.01 | 0.05 | 0.15 | 0.4 | |||
1.2.2 The content of impurities is guaranteed by the initial charge, the smelting technology, and the sum of impurities may be more than 0.4%, provided that the specified values for hardness and electrical conductivity of clause 1.1.8 are met.
1.2.3 During the smelting process, a technological additive in the form of a carbon fulleroid nanomodifier "Astralen" (TU 2166-001-13800624-2003) is introduced into the composition of the BrNHK(f) alloy.
1.3 Packaging
1.3.1 Forgings are supplied without packaging.
1.3.2 Forgings longer than 400 mm are supplied in bundles weighing no more than 500 kg, tied with packing tape GOST 19851-74.
1.4 Marking
1.4.1 The following information is applied to each forging:
- alloy grade;
- melt number;
- nominal dimensions;
- quality control stamp.
