In the present study, the self-healing behavior of Inconel 617B superalloy (617B), used as a high-temperature material, was investigated through both preliminary test consisting of room-temperature tension and annealing and creep rupture test. Micro-cracks in the solution-treated specimen, which had been fractured at room temperature, were filled in by the precipitation of M23C6 and the segregation of B, C, and S after annealing at 800 °C for 16 h. Due to this healing effect and dislocation recovery, a 33% pre-strained and annealed specimen exhibited the longer total elongation, compared to the specimen strained until fracture without annealing after 33% pre-strain. Finally, creep rupture tests revealed that the creep strength of 617B is higher than Inconel 617 superalloy (617) due to the self-healing effect by the high-temperature precipitation of M23C6 and the segregation of B, C, and S as well as grain boundary strengthening of B and C.
Bibliographical noteFunding Information:
We are thankful to Dr. Chang-Seok Oh (Korea Institute of Materials Science, Changwon), Mr. Young-Kwang Kim, and Professor Byeong-Joo Lee (Pohang University of Science and Technology, Pohang) for their assistances with thermodynamic calculations using Thermo-Calc software (database TTNI6). This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
© 2019 Elsevier B.V.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry