| Title |
High temperature Creep Behavior of AISI 304 Stainless Weldment |
| Authors |
이덕현(D . H . Lee); 권숙인(S . I . Kwun) |
| Abstract |
The effects of nitrogen and delta ferrite contents on 700℃ creep behavior of AISI 304 duplex weld metal under constant stress conditions were investigated. High ferrite weld metal showed a ductility almost as high as that of base metal under high stress. However, the ductility decreased sharply due to the sigma phase transformation under law stress. Distinct dislocation substructure was formed in high ferrite weld metal during creep deformation. On the other hand, the nitrogen in low ferrite weld metal formed nitrides during creep, which hindered dislocation motion and increased the creep strength remarkably. Activation energy for creep of weld metal increased with nitrogen content. This observation could be explained by a dynamic strain hardening effect and a decrease in diffusion rate due to nitrogen atoms. |