
Ignition
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For normal applications, alloys of nickel are used for the electrode material.
Chromium, manganese, silicon and magnesium are examples of the alloying
constituents. These alloys exhibit excellent properties with respect to corrosion
and burn-off resistance. To improve on the thermal conductivity, compound
electrodes are used. These allow a greater nose projection for the same
temperature range, as discussed in the last section. A common example of this
type of plug is the copper-core spark plug.
Silver electrodes are used for specialist applications as silver has very good
thermal and electrical properties. Again, with these plugs ...