| Title |
Creep Damage Evaluation for Simulated Weld Heat-Affected Zone in 12Cr-Mo-V Power Plant Steel |
| Authors |
정용근(Jeong Yong Geun); 강용호(Kang Yong Ho); 박종진(Park Jong Jin); 주철홍(Ju Cheol Hong); 박익민(Park Ig Min) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
12Cr-Mo-V steel; Welded joint; Simulated heat affected zone; Creep cavities; Plasticity constant; Creep strain rate |
| Abstract |
The creep rupture tests were carried out on actual welded joint specimens of 12Cr-Mo-V steel. It was revealed that the creep rupture life of actual welded joint was approximately 41% of that of base metal and the creep damage of it occurred mainly at intercritical heat-affected zone(HAZ). On the basis of the heat input during the welding, microstructure, microhardness and grain size of the actual intercritical HAZ, simulated HAZ was made in order to evaluate its material properties. The tensile tests and interrupted creep test were carried out on the simulated HAZ specimens. It was found that the tensile properties of the simulated HAZ were slightly inferior to those of the base metal and the creep rupture strength of it was approximately 46% of that of base metal and the creep strain rate of it was higher than that of base metal. The creep cavities in simulated HAZ were found at an early stage of creep life and the number of creep cavities increased exponentially and the average diameter of cavities increased linearly with creep life fraction. Plasticity constants of simulated HAZ can be available for the analysis of creep crack growth and the number and average diameter of creep cavities can be available for the evaluation of creep damage for welded joint. |