Scope
This information refers to silver based
contact material with tungsten carbide as
the second main component manufactured
by infiltration of molten silver into a
porous tungsten carbide preform.
DESIGNATION OF
STANDARD COMPOSITIONS
The tungsten carbide content is designated
by the first number e.g. AgWC50 in weight
percent. The standard percentages are
30,40 and 50.
Applications
- circuit breakers
- earth leakage breakers
- miniature circuit breakers
CHARACTERISTICS
Comparable with silver tungsten with
improved behaviour of contact resistance.
Tungsten carbide decomposes in the arc
and the released carbon forms a protective
CO gas envelope which suppresses the
formation of tungsten oxides
and tungstates.
MICROSTRUCTURE
AgWC
40
AgWC
50
Physical Properties
| Material |
AgW30 |
AgW40 |
AgW50 |
| Density [g/cm3] |
11.5 |
11.7 |
12.2 |
| Electrical Conductivity [m/(Ω.mm2)] |
36 |
34 |
29 |
| Hardness Soft [HRB] |
57 |
72 |
85 |