Sep 20 2012
Topics Covered
IntroductionChemical CompositionPhysical PropertiesMechanical PropertiesFabrication and Heat Treatment Machinability Welding Heat Treatment
Introduction
Copper is renowned for extremely good electrical and thermal conductivity. More than 400 varieties of copper alloys are available. Alloys can be freely formed using copper than by most metals.
The following datasheet gives an overview of UNS C90900 copper casting alloy.
Chemical Composition
The chemical composition of UNS C90900 copper alloy is tabulated below.
| Element |
Content (%) |
| Cu |
87 |
| Sn |
13 |
Physical Properties
The following table shows physical properties of UNS C90900 copper alloy.
| Properties |
Metric |
Imperial |
| Density |
8.74 g/cm3 |
0.316 lb/in³ |
Mechanical Properties
The mechanical properties of UNS C90900 copper alloy are outlined in the following table.
| Properties |
Metric |
Imperial |
| Hardness, Brinell ( 500 kg) |
90 |
90 |
| Tensile strength (as cast) |
276 MPa |
40000 psi |
| Yield strength (as cast) |
138 MPa |
20000 psi |
| Elongation at break ( as cast) |
15% |
15% |
| Machinability (UNS C36000 (free-cutting brass) = 100) |
20 |
20 |
| Poisson's ratio |
0.34 |
0.34 |
| Elastic modulus |
117 GPa |
17000 ksi |
Fabrication and Heat Treatment
Machinability
The machinability rating of UNS C90900 copper alloy is 20.
Welding
UNS C90900 copper alloy can be welded using brazing, soldering, oxyacetylene welding, gas shielded arc welding, coated metal arc welding, and carbon arc welding techniques.
Heat Treatment
UNS C90900 copper alloy can be stress relieved at the temperature of about 260°C (500°F). The time taken for stress relieving is 1 hr/in. of section thickness. It does not respond to heat treatment.