Abstract: Spark plug with an insulator, a center electrode placed in the insulator, a casing provided on the outside off the insulator and a casing electrode attached to the casing. The center electrode and/or the casing electrode are made using a platinum-nickel fiber composite material consisting of a platinum matrix in which nickel fibers are embedded or of a nickel matrix in which platinum fibers are embedded.

Abstract: Silver-nickel composite for electrical contacts and electrodes, particularly intended for spark plug electrodes. In order to prevent corrosive attack to the nickel components, the silver component consists of a silver alloy which is impervious to oxygen, and the nickel component is comprised of nickel or of a nickel alloy. This facilitates the manufacture of contacts and electrodes which have a long service life.

Abstract: In a spark plug with combined surface and air spark paths comprising a center electrode, and insulator which surrounds the center electrode and which, at least in the end region of the center electrode, maintains a gap with respect thereto, and a ground electrode which, together with the spark plug body, surrounds the insulator and which at least in the end region of the insulator maintains a gap with respect thereto, the insulator, to form a discharge chamber surrounding the end portion of the center electrode, extends in the axial direction of the plug beyond the center electrode, and the ground electrode encompasses the insulator around the end thereof with an extension of the ground electrode extending into the discharge chamber with a clearance gap being maintained between the extension and the end portion of the insulator.