高張力鋼の溶接部の組織と疲労切欠感受性について

概要

論文の詳細を見る
The fatigue notch sensitivity of steel has been reported to be raised by welding, though lowered value has also been appeared in another investigation. The present study was therefore undertaken in attempt to resolve the apparently paradoxical behavior. Considering the mean size of carbide, L', and its mean spacing, 2L, to be the main structural factors which influence the fatigue strength of steels, the authors has previously showed correlation between microstructure and fatigue behavior of quenched and tempered steels with and without notch. On this basis, the effect of microstructural change caused by welding on notched fatigue strength of welded steel was investigated. It is found that the notch sensitivity can be raised or lowered according to the metallurgical change at welded part. That is for a given steel with lowere value of L_b (Suffix b refers to base metal), the fatigue notch sensitivity is generally raised by welding. On the other hand, the notch sensitivity of welded part is not so affected by welding in case the value of L_b is small such as high strength steels. Moreover, it is expected to be lower notch sensitivity of welded part if L_w (Suffix w refers to weld part) is larger than L_b.
社団法人溶接学会の論文
1974-08-05