高周波抵抗溶接における冷接が延性及び破壊靱性に及ぼす影響とその評価

抄録

Influence of the weld oxides on the ductility and fracture toughness of the elect ric resistance welded joint of steel pipewas investigated. Experiments were performed for round bar tensile tests and three point bend COD test. With the increase of the oxides zone area which was defined by fracture appearance, the ductility in the smooth and the notched bar specimens, and the fracture toughness were gradually decreased. Fractographic examination showed a good correlation between the stretched zone depth in COD specimen and the dimple size at the oxides zone. Finally, the validity of engineering evaluation method for the weld oxides was discussed.