| 摘要 |
[Objective] An objective of the present invention is to provide a technique which can improve resistance to spark ablation of an electrode tip whose predominant component is Pd and restrains occurrence of separation and cracking of the electrode tip. [Means for solution] The electrode tip located at an distal end of an electrode of a spark plug contains Pd as a predominant component in an amount of 40 wt.% or more; at least one element of Ir, Ni, Co, and Fe, wherein, when the tip contains Ir, the amount of Ir is 0.5 wt.% to 20 wt.%, and when the tip contains at least one element of Ni, Co, and Fe, the amount of the at least one element is 0.5 wt.% to 40 wt.%; and at least one element of Pt, Re, Rh, and Ru in a total amount of 5 wt.% to 40 wt.%, wherein when the tip contains at least one element of Re, Rh, and Ru, the amount of the at least one element is 10 wt.% or less, and when the tip contains Pt, the amount of Pt is 16 wt.% to 40 wt.%. |
