80kg/mm2級高張力鋼の溶接割れ感受性におよぼすBの影響
1974 年 60 巻 9 号 p. 1373-1379
詳細
1974 年 60 巻 9 号 p. 1373-1379
This paper showed the effect of B on the delayed fracture of high strength steels. As the result of many cold cracking tests in welding (Tekken-type etc.), three characteristic facts were indicated. Firstly, B is very effective in preventing cold cracking. Secondly, B segregates at austenite grain boundaries in heat affected zone. Thirdly, diffusion of hydrogen becomes slower when B segregates at austenite grain boundaries. From these facts it is thought that the diffusion of hydrogen to stress-concentrated region is suppressed by B in heat affected zone and thus B is beneficial in preventing cold cracking and makes steels insensitive to cold cracking.
