摘要 |
A friction stir welding method for joining steel sheets to one another by moving a rotating tool (10) along a section to be joined while inserting and rotating the same into the section to be joined, where two or more steel sheets overlap or abut one another, and using the softening of the steel sheets caused by friction heat between the rotating tool (10) and the steel sheets, and the plastic flow caused by stirring, wherein, according to the present invention, heating devices (4), which are positioned above and below the section to be joined so as to sandwich the same, and positioned to the front in the direction of travel of the rotating tool (10), pre-heat the section to be joined prior to the joining by the rotating tool (10). Consequently, it is possible to join quickly without any risk of joining failures or joining-tool breakage. |