Evaluation of self-welding susceptibility of an austenitic stainless steel (alloy D9) in sodium

Effect of cold-work on self-welding susceptibility of austenitic stainless steel (alloy D9) in high temperature flowing sodium

“…It is earlier reported that during testing, specimens pick up carbon from the flowing sodium and there is slight increase in carbon content and hardness at the specimen surface [6,7]. Decoration of austenite grain boundaries with carbides near the specimen surface has also been established.…”

“…Microstructures of annealed and 20% cold-worked alloy D9 before testing are compared in Fig. 8 [6]. In the annealed specimens, annealing twins are observed and in the cold-worked specimen twin density is much higher than the other and these twins are generated due to coldwork.…”

“…Hence, microstructure at locations C and E were examined under SEM to find out whether there is 8. Microstructure of (a) annealed D9 and (b) 20% cold-worked alloy D9 specimens before self-welding susceptibility studies [6].…”

“…Agastini has studied self-welding in 20% cold-worked AISI 316 stainless steel [5]. Recently self-welding studies on annealed and cold-worked alloy D9, and 316LN austenitic stainless steel [6,7] were reported by our team.…”

Self-welding susceptibility of cold worked alloy D9 and 316LN austenitic steels in flowing sodium

“…Yokota and Shimoyashiki, 2 Huber and Mattes, 3 Yoshida et al 4 and Agostini and Masetti 5 studied the susceptibility of 304, 316 and 321 austenitic stainless steel, and our team studied the self-welding of alloy D9 and 316LN austenitic stainless steels. [6][7][8] It was observed in the previous studies that under identical conditions of testing, the mating surfaces of annealed alloy D9 did not exhibit self-welding, while the mating surfaces of annealed 316LN specimens self-welded. Further, testing of cold worked alloy D9 specimens revealed that self-welding does occur in the cold worked condition, though the experimental conditions in which these tests were carried out simulate conditions more severe than what is expected during reactor (prototype fast breeder reactor) operation.…”