| 摘要 |
PROBLEM TO BE SOLVED: To provide a welded structure of steel, which can securely suppress the generation of fatigue damage such as a fatigue crack in a weld portion.SOLUTION: In a welded structure A of steel, hammer peening or ultrasonic shock processing is applied in the surface of a base material 1 adjoining a weld bead 3 using a tool 6 for forming an impact trace to form an impact trace 5. The tool 6 for forming the impact trace has an impact trace forming surface 7 which is formed to be a circular shape which is flat and the radius of which is 1.5 mm or more, 3.0 mm or less in the front end thereof. The impact trace 5 of which the maximum depth is 0.03 mm or more, 0.50 mm or less, is formed continuously along the weld bead 3 in the zone from the toe 4 of the weld bead 3 to 5 mm in the base material 1 side. |
