Abstract: A spark plug, especially one for a gas-fueled internal combustion engine has an electrically conducting spark plug body (1), a central electrode (3) which is located in the spark plug body (1) and which is electrically insulated from and projects away from the spark plug body (1), and a ground electrode (4) which is electrically connected to the spark plug body (1) and is made in the form of an annular electrode. The annular electrode (4) surrounds the front part of central electrode (3) such that an annular ignition gap (ZS) is formed between them. Surfaces of the central electrode (3) and the annular electrode (4) bordering the ignition gap (ZS) are provided with precious metal armorings in the form of sleeves (5, 6,), especially of platinum or a platinum alloy. This yields a spark plug with an extremely long service life.

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.