| Title |
Fracture Toughness Evaluation of a Low Toughness Weldment of Reactor Pressure Vessel Steel by Ball Indentation Tests in the Transition Region |
| Authors |
조한서(Han Seo Cho),양원존(Won Jon Yang),이봉상(Bong Sang Lee),홍준화(Jun Hwa Hong) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Abstract |
Fracture toughness of the weldment of a pressure vessel steel was evaluated by ABI(automated ball indentation) tests in the transition temperature region. The evaluation procedure was based on the semi-empirical IEF(indentation energy to fracture) theory that has been recently developed using two basic assumptions. One is that the triaxial stress state beneath the ball indenter is similar to that of a crack tip ahead. Second, the fracture stress of a material is almost temperature-independent in case the stress-controlled cleavage fracture occurs. The fracture toughness characteristics determined by ABI tests were comparable to those obtained by standard 3-point bending tests. The multi-passed weldment was divided into two parts by their macroscopical appearances; as-solidified region and recrystallized one. However, both regions did not show a significant difference in fracture toughness as well as hardness and flow properties in the tested material. |