Method for Producing Plug

Abstract

A method for producing a plug includes: a step of preparing a plug base metal having a concave portion along a circumferential direction in an outer peripheral surface; and an arc spraying step of spraying a spraying wire rod material onto the outer peripheral surface of the plug base metal by arc spraying to form films containing Fe and Fe oxides on the outer peripheral surface of the plug base metal. The arc spraying step includes: a separating step of separating the outer peripheral surface of the plug base metal into a plurality of regions along an axial direction; and a step of performing arc spraying separately in each of the regions. In the separating step, a boundary between the regions is set at the concave portion. In this way, peeling of films at a connecting portion is prevented, and the lifetime of the plug can be increased.

Dependencies are inferred from the claim text.