| 摘要 |
A spark plug (1) includes: a center electrode (5); an insulator (2); a main metal fitting (3); an earth electrode (27); and a noble metal chip (32) provided to a part of at least one of the center electrode (5) and the earth electrode (27). An edge face side of the noble metal chip (32) is joined to the part via a melting section (35). The melting section (35) includes: a first melting section (351) formed by radiating a laser beam or the like, along the circumferential direction of the noble metal chip (32), on a boundary between the edge face of the noble metal chip (32) and the part; and a second melting section (352) formed by radiating a laser beam or the like from the side where the laser beam or the like is radiated when the first melting section (351) is formed, the second melting section (352) intersecting with the first melting section (351). Accordingly, it is possible to sufficiently exert an effect of improving wear resistance by providing the noble metal chip and to effectively suppress separation of the noble metal chip. |
