Aug 6 2013
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Other Designations
Fabrication
Machinability
Welding
Cold Working
Applications
Introduction
WHA alloys are manufactured by powder metallurgy. They are known by the commercial name of Densalloys. Densalloys are grouped into four classes, with each class further divided into two sub-classes. Classes 1-3 consist of magnetic and non-magnetic subdivision, while class 4 is only magnetic. The magnetic permeability is the bases for classifying as magnetic (permeability <1.05) and non-magnetic (permeability≤1.05).
SD180 is a WHA alloy belonging to Class 3 having a magnetic permeability of 4-4.5. The magnetic permeability of this alloy is much higher than 1.05, hence it is considered magnetic. The tungsten content of this alloy is 95% and the rest is composed of iron and nickel. The standard forms in which the alloy is available are pressed and sintered billet, sintered near net shape, sheet and plate.
This datasheet will look into the chemical composition, properties and applications of Densalloy-SD180.
Chemical Composition
The chemical composition of Densalloy SD180 is given in the following table.
|
Element |
Content (%) |
|
Tungsten, W |
95 |
|
Nickel, Ni |
3.5 |
|
Iron, Fe |
1.5 |
Physical Properties
The following table discusses the physical properties of Densalloy SD180.
|
Properties |
Metric |
Imperial |
|
Density |
18.13 gm/cm3 |
0.655 lb/in3 |
Mechanical Properties
The mechanical properties of Densalloy SD180 are tabulated below.
|
Properties |
Metric |
Imperial |
|
Tensile strength |
827MPa |
120 ksi |
|
Yield strength |
517 MPa |
75 ksi |
|
Elongation at Break (1 inch (2.5 cm) gauge length) |
4% |
4% |
|
Hardness, Rockwell C |
≤34 |
≤34 |
Other Designations
Some of the designations used to denote Densalloy SD180 are listed below:
-
MIL-T-21014D
-
ASTN B777-87
Fabrication
Machinability
SD180 alloy is easily machinable into complex shapes using common metal cutting and shaping tools. A suitable coolant should be used while machining this alloy.
Welding
These alloys cannot be welded due to the vast difference in the welding and binder phase.
Cold Working
This alloy can be cold worked by the process of swaging.
Applications
Densalloy SD180 is used in the following applications:
-
Radiation shielding
-
Aircraft counter balances
-
Racing weights
-
Boring bars
-
Ordnance applications
-
Well lodging.