| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a welded joint having fatigue characteristics capable of enduring to the vibration of a giga-cycle range and also having sufficient fracture toughness. <P>SOLUTION: The welded joint includes a pair of steel materials and a weld metal formed at the butt-welded part between the pair of steel materials by welding by a beam having high energy density where the content of C in the pair of steel materials is within a range of 0.01-0.08 mass%, and the weld metal has a transformation initiation temperature Ms of ≤250°C calculated by a following equation (a) using the composition (mass%) of the weld metal, and compressive residual stress is imparted to the butt-welded part. The equation (a): Ms(°C)=371-353C-22Si-24.3Mn-7.7Cu-17.3Ni-17.7Cr-25.8Mo. <P>COPYRIGHT: (C)2012,JPO&INPIT |
