| 摘要 |
PROBLEM TO BE SOLVED: To provide a peening method which improves fatigue strength by introducing compressive residual stress without giving deformation causing another stress concentrating part to a welding part, and is suitable for applying a steel structure such as a steel bridge in which excellent fatigue characteristics is required.SOLUTION: In a peening method for a welding part, impact dents are continuously formed along a welding bead on the surface of a steel material of a weld toe by a vibrating terminal. The vibrating terminal is an almost rectangular shaped body whose top of tip end part has an arc shape, and the tip end part has a length of 1-10 mm in the direction of movement, and the top has, in a cross section rectangular to the movement direction, a center of curvature decentered from the center of width of the vibrating terminal to the weld toe side, and has an arc shape having a curvature radius of 1-5 mm, and the impact dents whose maximum depth is not less than 0.03 mm and less than 0.50 mm are formed in a region of 5 mm from the weld toe to a base material side. |
