Patent ID: 7832615
Filing Date: 2010-11-16
Classification: B23K

Abstract:
1. A joining method, in which a first metal member and a second metal member that lap over are provided, a metal plating being applied at least on a joining portion of the first metal member, a melting point of the second metal member being lower than that of the first metal member, and a rotating tool under rotation is pressed against the second metal member and the second metal member is softened into a plastic flow state by a frictional heat generated through a rotating and pressing operation of the rotating tool, whereby the first and second metal members are joined in a solid state, the joining method comprising: a step of heating said metal plating applied on the joining portion of the first metal member before the rotating tool under rotation is pressed against the second metal member; a step of detecting the temperature of the metal plating heated in said heating step; a step of setting a pressing timing of the rotating tool under rotation against the second metal member when the temperature of the metal plating detected in said detecting step reaches a specified temperature that is high enough to set the metal plating in a softened solid state; a step of starting pressing of the rotating tool under rotation against the second metal member at the pressing timing set in said setting step; and a step of pushing out the metal plating softened in said heating step from a joining boundary portion between the first and second metal members through the rotating and pressing operation of the rotating tool, whereby the first and second metal members are joined in the solid state substantially without said metal plating and with a direct contact of new uncovered surfaces of the metal members at the joining boundary portion of the metal members.