Sep 20 2012
Topics Covered
IntroductionChemical CompositionPhysical PropertiesMechanical PropertiesThermal PropertiesOther DesignationsFabrication and Heat Treatment Machinability Welding Hot Working Cold Working AnnealingApplications
Introduction
Pure copper has good electrical and thermal conductivity. More than 400 varieties of copper alloys are available. UNS C75700 nickel silver 65-12 copper alloy has good corrosion and tarnish-resistance, and high formability. It is available as wire and flat products.
The following datasheet gives details about UNS C75700 copper alloy.
Chemical Composition
The following table shows the chemical composition of UNS C75700 copper alloy.
| Element |
Content (%) |
| Cu |
65 |
| Zn |
23 |
| Ni |
12 |
Physical Properties
The physical properties of UNS C75700 copper alloy are tabulated below.
| Properties |
Metric |
Imperial |
| Density |
8.69 g/cm3 |
0.314 lb/in³ |
Mechanical Properties
The mechanical properties of UNS C75700 copper alloy are outlined in the following table.
| Properties |
Metric |
Imperial |
| Tensile strength |
359-641 MPa |
52100-93000 psi |
| Yield strength (depending on temper) |
124-545 MPa |
18000-79000 psi |
| Elongation at break (in 50.8 mm) |
48% |
48% |
| Elastic modulus |
117 GPa |
17000 ksi |
| Poisson’s ratio |
0.34 |
0.34 |
| Machinability (UNS C36000 (free-cutting brass) = 100) |
20 |
20 |
| Shear modulus |
47 GPa |
6820 ksi |
Thermal Properties
The thermal properties of UNS C75700 copper alloy are given in the following table.
| Properties |
Metric |
Imperial |
| Thermal expansion co-efficient (@ 20-300°C/68-572°F) |
16.2 µm/m°C |
9.00 µin/in°F |
| Thermal conductivity (@20°C/68°F) |
40 W/mK |
278 BTU in/hr.ft.°F |
Other Designations
Other designations that are equivalent to UNS C75700 copper alloy include:
- ASTM B151
- ASTM B206
- QQ W321
Fabrication and Heat Treatment
Machinability
The machinability rating of UNS C75700 copper alloy is 20.
Welding
UNS C75700 copper alloy can be welded using brazing, soldering, gas shielded arc welding, seam welding, spot welding, and oxyacetylene welding techniques. Coated metal arc welding technique is not preferred for welding this alloy.
Hot Working
UNS C75700 copper alloy has poor hot forming capacity.
Cold Working
UNS C75700 copper alloy has good cold working capacity.
Annealing
UNS C75700 copper alloy can be annealed at temperatures ranging from 594 to 816°C (1100 to 1500°F).
Applications
UNS C75700 copper alloy is used in the following applications:
- Musical instrument valves and components
- Jewelry
- Slide fasteners
- Optical instrument components
- Fittings for food and dairy equipment
- Screws
- Rivets
- Decorative items