MATERIAL FOR SPARK PLUG ELECTRODES AND METHOD FOR PRODUCING SAME

The present invention discloses a material for spark plug electrodes, which is composed of a base material that is formed of Ir or an Ir alloy and an oxidation prevention film that covers the surface of the base material. A base layer that is formed of Au is formed on the surface of the base material that is formed of Ir or an Ir alloy; and an Ni film having a thickness of from 3.0 [mu]m to 8.0 [mu]m (inclusive) is formed, as the oxidation prevention film, on the base layer. This Ni film turns into an oxidation prevention film that is formed of Ni oxide in an oxidizing atmosphere at 500 DEG C or higher. Because of this oxidation prevention film, the material for spark plug electrodes according to the present invention has excellent high-temperature oxidation characteristics. 本发明公开了包含由Ir或Ir合金构成的基材和覆盖所述基材表面的防氧化膜的火花塞电极用材料。在此，在由Ir或Ir合金构成的基材上，在表面形成有由Au构成的基底层，在其上形成有厚度为3.0μm以上且8.0μm以下的Ni膜作为防氧化膜。该Ni膜在500℃以上的氧化性气氛中形成由氧化Ni构成的防氧化膜。利用该防氧化膜，本发明的火花塞电极用材料具有优良的高温氧化特性。