| Project/Area Number |
18H01739
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Review Section |
Basic Section 26040:Structural materials and functional materials-related
|
|---|
| Research Institution | Kyushu University |
|---|
Principal Investigator |
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
山崎 重人 九州大学, 工学研究院, 准教授 (00804741)
光原 昌寿 九州大学, 総合理工学研究院, 准教授 (10514218)
|
|---|
| Project Period (FY) |
2018-04-01 – 2021-03-31
|
| Project Status |
Completed (Fiscal Year 2020)
|
| Budget Amount *help |
¥17,550,000 (Direct Cost: ¥13,500,000、Indirect Cost: ¥4,050,000)
Fiscal Year 2020: ¥3,380,000 (Direct Cost: ¥2,600,000、Indirect Cost: ¥780,000)
Fiscal Year 2019: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000)
Fiscal Year 2018: ¥11,050,000 (Direct Cost: ¥8,500,000、Indirect Cost: ¥2,550,000)
|
|---|
| Keywords | クリープ / 亜粒界 / 耐熱鋼 / 微細組織 / 変形理論 / 変形機構 |
|---|
| Outline of Final Research Achievements |
The purpose of this study is to elucidate the mechanism of subgrain boundary strengthening in creep deformation. For ferritic heat-resistant steels, a resistance theory model based on subgrain boundaries was constructed by applying the test methods and theoretical handling established for high-temperature deformation of solid solution reinforced alloys. We succeeded in measuring ultra-low strain rate creep deformation on the order of 10-10 s-1 by our original ultra-high precision uniaxial creep test. From this, it was clarified that the stress dependence of the minimum strain rate differs between high stress region and low stress region. In addition, as a result of performing a stress sudden change test by the ultra-high precision creep test method, it was clarified that instantaneous plastic strain occurs, and that ferritic heat-resistant steel exhibits deformation behavior controlled by internal stress.
|
| Academic Significance and Societal Importance of the Research Achievements |
本研究により、フェライト系耐熱鋼における亜粒界強化メカニズムは高応力域と定応力域で異なることが明らかとなった。このことは同材料の実用応力域とこれまで加速試験が行われていた応力域では変形メカニズムが異なることを意味しており、今後、実用条件下での同材料の余寿命予測において重要な知見となることが期待される。
|
