Friction agitation joining method, method for manufacturing joined butted members and friction agitation joining apparatus

Abstract

In a friction agitation joining method, two plate-shaped joining members different in thickness, or first and second joining members, are abutted against each other with a level difference formed at upper surface sides thereof. A rotating probe of a joining tool is inserted into the butted portion of the first and second joining members from upper surface sides thereof. Joining-direction front sides of the first and second joining members with respect to the probe inserted position are pressed by first and second front pressing rollers, respectively, from the upper surface sides thereof. Furthermore, joining-direction lower sides of the first and the second joining members with respect to a probe inserted position from the upper surface sides are pressed by first and second lower pressing rollers, respectively, from the upper surface sides thereof. In this state, the butted portion is joined by the friction agitation joining method.