| 摘要 |
PROBLEM TO BE SOLVED: To provide a friction joining method capable of enhancing the joining strength by increasing the ductility of a joined portion when joining a plurality of steel members by the friction joining. SOLUTION: The friction joining method in which a first steel member W1 overlaps a second steel member W2, the first and second steel members are softened and subjected to the plastic flow by the friction heat generated by pressing a rotary tool 10 thereagainst in a rotating manner, and the first and second steel members are joined with each other, comprises a joining step of forming a joined part M in which the first and second steel members are joined with each other, and a cooling step of cooling the joined part which is formed in the joining step and heated by the friction heat generated by pressing the rotary tool thereagainst. In the cooling step, the joined part is heated by a high-frequency heating means 22 so as to avoid generation of a martensitic structure at the joined part, and the joined part is slowly cooled. COPYRIGHT: (C)2008,JPO&INPIT |
