CuSn12Ni2

What Is CuSn12Ni2?

CuSn12Ni2 is a copper-based cast tin bronze containing 11-13% tin and 1.5-2.5% nickel. Under the current EN 1982:2024 standard, it is designated CuSn12Ni2-C / CC484K for cast products and CuSn12Ni2-B / CB484K for the related ingot.

Tin provides hardness and wear resistance, while nickel contributes to mechanical strength, corrosion resistance and stability under demanding service conditions. Compared with CuSn12-C, it is intended for applications where high surface pressure, wear and corrosion act together.

Chemical Composition

Under EN 1982:2024, CuSn12Ni2-C / CC484K contains 84.5-87.5% Cu, 11.0-13.0% Sn, 1.5-2.5% Ni and 0.05-0.40% P. Maximum limits are 0.30% Pb, 0.40% Zn, 0.20% Fe and Mn, 0.10% Sb, 0.05% S, and 0.01% Al and Si. For this alloy, Cu and Ni are stated separately; the copper value is not expressed as a Cu + Ni total.

Mechanical and Typical Physical Properties

EN 1982:2024 reference minimums are shown for sand casting as 280 MPa tensile strength, 160 MPa proof strength, 12% elongation and 85 HBW; for centrifugal casting as 280 MPa, 180 MPa, 8% and 95 HBW; and for continuous casting as 300 MPa, 180 MPa, 10% and 95 HBW, respectively.

Typical values are approximately 8.6 g/cm³ density, 0.376 J/(g·K) specific heat, 17.5 × 10⁻⁶/K coefficient of thermal expansion, 54 W/(m·K) thermal conductivity and 6.2 MS/m electrical conductivity. Physical properties are typical references and must not be treated as guaranteed product values.

Properties and Applications

CuSn12Ni2 is distinguished by high wear resistance, good toughness, the ability to carry high surface pressures, and resistance to cavitation and corrosion. Although it has good seawater resistance, final material selection must consider fluid composition, temperature, flow velocity and mating materials.

Principal applications include heavily loaded worm wheels, heavy-duty gears, plain bearings operating at low to moderate speeds, bronze bushings, sliding elements, loaded spindle nuts, pump housings and impellers, valve and fitting components, elevator and escalator drives, and suitable machine components exposed to seawater.

The alloy should not be assumed to run without lubrication in every application. Lubricant selection must be evaluated together with counterface hardness and finish, operating clearance, load, speed, temperature and environmental conditions. Machinability should be regarded as moderate to difficult, requiring suitable tooling and cutting parameters.

Production and Supply Forms

KUPTİN® Nİ can be produced by centrifugal casting, continuous casting, sand casting and project-specific casting. The process is selected according to product form, dimensions, part geometry, required mechanical properties, service conditions and the order specification.

The alloy can be supplied as round bar, bronze bushing, tube, hollow or solid component, ring, flat bar, plate, special section and casting made to technical drawings. Final dimensions, tolerances and machining allowances should be evaluated before ordering.

Standards and Comparable Grades

The primary European designation for CuSn12Ni2 cast products is CuSn12Ni2-C / CC484K under EN 1982:2024. CuSn12Ni2-B / CB484K is the related ingot designation and must not be used as though it were the casting product grade.

Former DIN 1705 designations are G-CuSn12Ni / 2.1060.01 for sand casting, GZ-CuSn12Ni / 2.1060.03 for centrifugal casting and GC-CuSn12Ni / 2.1060.04 for continuous casting. CT2 is a historical comparable designation under the former BS 1400 standard. CuSn12Ni2 under ISO 1338:1977 should also be treated only as a historical reference.

UNS C91700 is a comparable US grade, but it is not a direct equivalent because its tin, nickel, phosphorus and other composition limits differ. ASTM B427 is a product specification for gear bronze alloy castings including C91700. ASTM B505/B505M-23 covers continuous cast copper-alloy products, but C91700 is not included in its current alloy table and has therefore not been used here as the primary ASTM reference. C90800, C92500 and C93200 have different compositions and have been excluded from the equivalents list.

Technical Note

The values in section 02, Mechanical Properties, are minimum references shown separately by casting process. Mechanical results can vary with section size, specimen location and casting structure; requirements for the final component section must be agreed with the manufacturer when ordering. The chemical, mechanical and physical information provided here is for general technical guidance. Final product properties must be verified against the order specification, casting process, section size, dimensions, tolerances, product analysis certificate and quality-control results.