鉄鋼溶接部における硫化物の挙動と凝固割れ(第5報)
低炭素鋼溶接金属(C≦0.12%)の凝固割れ感受性についての理論的ならびに実験的検討
1974 年 43 巻 1 号 p. 57-65
詳細
1974 年 43 巻 1 号 p. 57-65
Effects of S, Mn and P on solidification crack in weld metals of plain crabon steels containing not more than 0.12% carbon and Fe-S-Mn ternary alloys have been investigated by Trans-Varestraint and Modified Trans-Varestraint tests. Further the relation between Mn and S contents to minimize the solidification crack susceptibility has been theoretically deduced, and this relation has been experimentally confirmed. Main conclusions obtained are as follows:
1) Both S and P promote the solidification crack. The effect of P, however, is negligible in comparison with that of S.
2) Mn is an effective element to prevent the detrimental effect of S.
3) Relation between Mn and S contents to minimize the solidification crack susceptibility has been theoretically deduced by combining the changing curve in composition and Fe-(Mn, Fe) S eutectic temperature. This relation is represented as follows;
Mn3/S>6.7
This relation is confirmed by Trans-Varestraint test. Brittleness temperature range (BTR) in weld metal which satisfies the above relation is 30-40°C.
