| Project/Area Number |
19F19775
|
|---|
| Research Category |
Grant-in-Aid for JSPS Fellows
|
| Allocation Type | Single-year Grants |
|---|
| Section | 外国 |
|---|
| Review Section |
Basic Section 26040:Structural materials and functional materials-related
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
阿部 英司 東京大学, 大学院工学系研究科(工学部), 教授 (70354222)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
GUAN KAI 東京大学, 工学(系)研究科(研究院), 外国人特別研究員
|
|---|
| Project Period (FY) |
2019-11-08 – 2022-03-31
|
| Project Status |
Completed (Fiscal Year 2021)
|
| Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 2021: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2020: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 2019: ¥600,000 (Direct Cost: ¥600,000)
|
|---|
| Keywords | Mg合金 / 電子顕微鏡 / 微細組織 / 元素偏析 / 溶質クラスタリング |
|---|
| Outline of Research at the Start |
The objective is to develop ultra-high strength Mg alloys through the co-additions of RE elements in them. In addition, the mechanism of co-addition responsible for influencing the mechanical properties of ultra-high strength Mg-RE-based alloys will be clarified.
|
| Outline of Annual Research Achievements |
Microstructures of several rare-earth (RE)-containing Mg alloys have been investigated systematically from micron-scale to atomic scale using electron microscopy. The major results focusing on unique long-period stacking/order (LPSO) atructures are summarized as follows.
1) Short-range order (SRO) solute clusters in the LPSO phases with an intrinsic-I (I1) type stacking faults (SFs), which have been uniquely formed in Mg-Co-Y alloys, are investigated. The Co3Y5 SRO cluster model embedded across the I1-type SFs has been successfully constructed to satisfy the observed electron diffraction, STEM images and computed energetic stabilities. The optimized Co3Y5 cluster configurations appear to be significantly deviated from the host Mg atom positions and consequently provide a significant gain for the energetic stability of the I1-type LPSO phases.
2)In a MgHo2.0Cu0.4Zr0.1 alloy, it is found that 18R, 14H and 24R LPSO phases coexist with fully coherent interfaces along step-like composition gradient in a blocky intermetallic compound distributed at grain boundaries. Importantly, the estimated chemical compositions of solute-enriched stacking-fault (SESF) in all LPSO variants are almost identical with the ideal SESF composition of 9M in-plane order, regardless of the type of LPSO phases. The results support the viewpoint that the robust L12-type SRO TM6RE8 clusters play an important role in governing LPSO phase formation.
|
| Research Progress Status |
令和3年度が最終年度であるため、記入しない。
|
| Strategy for Future Research Activity |
令和3年度が最終年度であるため、記入しない。
|
