2017 Fiscal Year Final Research Report
Toughening of precipitation strengthening steels with core-shell structured precipitates
| Project/Area Number |
16K14422
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| Research Category |
Grant-in-Aid for Challenging Exploratory Research
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| Allocation Type | Multi-year Fund |
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| Research Field |
Structural/Functional materials
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| Research Institution | Kyushu University |
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Principal Investigator |
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| Co-Investigator(Kenkyū-buntansha) |
赤間 大地 九州大学, 工学研究院, 特任助教 (80612118)
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| Project Period (FY) |
2016-04-01 – 2018-03-31
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| Keywords | 析出制御 / その場析出 / 相変態 / 機械的性質 |
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| Outline of Final Research Achievements |
The heat treatment process was investigated to form core-shell structured precipitates composed of hard VC (core) and soft Cu (shell) particles in Fe-2Cu-0.9V-0.19C alloy. Firstly, VC was precipitated within martensite matrix through quenching and tempering, and then the specimen was heated in the VC+austenite two-phase region, followed by austenite to ferrite phase transformation at various cooling rates to make Cu precipitate on the surface of pre-existing VC. It was found that Cu underwent in-situ precipitation on VC when the cooling rate is slow. However, Cu tended to preferentially grow in a specific crystallographic direction after the nucleation. The method to control the morphology of Cu would be the next subject to be solved in future.
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| Free Research Field |
鉄鋼材料
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