| 摘要 |
The present invention advantageously overcomes poor plastic flow due to insufficient heating of a material to be processed, to obtain sufficient strength and improve joining workability. The friction stir welding apparatus according to the present invention performs a preheating treatment process in which a steel sheet, which is a material to be processed, is heated by a heating device provided in front of a rotary tool that moves in a joining direction, and strictly controls the surface temperature, the area, the position, and the like, of a heating region in the preheating treatment process, when friction stir welding of structural steel is performed. |
