2013 Fiscal Year Final Research Report
Creep degradation assessment for creep-strength-enhanced ferritic steels by positron annihilation spectroscopy
Project/Area Number |
24760573
|
Research Category |
Grant-in-Aid for Young Scientists (B)
|
Allocation Type | Multi-year Fund |
Research Field |
Structural/Functional materials
|
Research Institution | Tohoku University |
Principal Investigator |
INOUE Koji 東北大学, 金属材料研究所, 准教授 (50344718)
|
Project Period (FY) |
2012-04-01 – 2014-03-31
|
Keywords | 陽電子消滅 / クリープ |
Research Abstract |
Creep degradation of creep-strength-enhanced ferritic steels was studied by positron lifetime spectroscopy. Creep time dependence of mean positron lifetime consists of three regions that are decrease in initial stage, gradual decrease in middle stage, and large decrease before rupture. These regions almost correspond to transient, steady-state, and accelerating regions, respectively. Furthermore, increase of the mean positron lifetime in the initial creep time from that before creep test corresponds to formation of precipitates during the creep test in the steels. Creep life assessment by the mean positron lifetime is demonstrated.
|