Sep 27 2012
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Thermal Properties
Other Designations
Fabrication and Heat Treatment
Machinability
Welding
Hot Working
Cold Working
Annealing
Applications
Introduction
Copper-nickel alloys have very good resistance to biofouling and
marine corrosion, and possess good fabricability. Copper gains more
strength and corrosion resistance when nickel is added to it.
UNS C71500 copper-nickel (cupronickel) alloy has medium high
strength and good creep resistance at high temperatures. This alloy is
expensive in comparison with copper-aluminum alloys and other alloys
with similar mechanical properties.
The following datasheet will provide more details about the UNS
C71500 cupronickel-copper nickel alloy.
Chemical Composition
The following table shows the chemical composition of UNS C71500
cupronickel alloy.
| Element |
Content
(%) |
| Copper, Cu |
70 |
| Nickel, Ni |
30 |
Physical Properties
The physical properties of UNS C71500 cupronickel alloy are outlined
in the following table.
| Properties |
Metric |
Imperial |
| Density |
8.94 g/cm3 |
0.323 lb/in3 |
| Melting point |
1171°C |
2140°F |
Mechanical Properties
The mechanical properties of UNS C71500 cupronickel alloy are
tabulated below.
| Properties |
Metric |
Imperial |
| Tensile strength |
372-517 MPa |
54000-75000 psi |
| Yield strength (depending on temper) |
88.0-483 MPa |
12800-70100 psi |
| Elongation at break (in 381 mm) |
45% |
45% |
| Elastic modulus |
117 GPa |
17000 ksi |
| Poisson’s ratio |
0.34 |
0.34 |
| Machinability (UNS C36000
(free-cutting brass) = 100) |
20 |
20 |
| Shear modulus |
57.0 GPa |
8270 ksi |
Thermal Properties
The thermal properties of UNS C71500 cupronickel alloy are tabulated
below.
| Properties |
Metric |
Imperial |
| Thermal expansion co-efficient
(@20-300°C/68-572°F) |
16.2 µm/m°C |
9 µin/in°F |
| Thermal conductivity (@20°C/ 68°F ) |
29 W/mK |
201 BTU in/hr.ft².°F |
Other Designations
Equivalent materials to UNS C71500 cupronickel alloy are:
| ASME SB111 |
ASTM B111 |
ASTM B466 |
MIL C-15726 |
| ASME SB171 |
ASTM B122 |
ASTM B543 |
MIL T-15005 |
| ASME SB359 |
ASTM B151 |
ASTM B552 |
MIL T-16420 |
| ASME SB395 |
ASTM B171 |
ASTM B608 |
MIL T-22214 |
| ASME SB466 |
ASTM B359 |
ASTM F467 |
SAE J461 |
| ASME SB467 |
ASTM B395 |
ASTM F468 |
SAE J463 |
| ASME SB543 |
ASTM B432 |
DIN 2.0882 |
Fabrication and Heat Treatment
Machinability
The machinability rate of UNS C71500 cupronickel nickel alloy is 20.
Welding
Soldering, brazing, oxyacetylene welding, gas shielded arc welding,
coated metal arc welding, spot welding, seam welding, and butt welding
are considered as suitable welding processes for UNS C71500 alloy.
Hot Working
The hot working capacity of UNS C71500 copper nickel alloy is rated
as good with the suitable hot working temperature being between 927 and
1038°C (1700 and 1900°F).
Cold Working
The cold working capacity of UNS C71500 is good.
Annealing
The annealing temperature of UNS C71500 copper nickel alloy is
between 649 and 816°C (1200 and 1500°F).
Applications
The UNS C71500 cupronickel alloy is primarily used in seawater
operations requiring forged and machined pump and valve components,
hardware and fittings. This alloy can also be widely used in areas
requiring high corrosion resistance, and where chloride
stress-corrosion cracking precautions prevent usage of stainless steels.