1998 Fiscal Year Final Research Report Summary
Prediction of High-temperature Creep Deformation for Precipitation Hardened Aollys
| Project/Area Number |
08650809
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Structural/Functional materials
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| Research Institution | Akita University |
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Principal Investigator |
GOTO Shoji Akita University Faculty of Engineering and Resource Science Professor, 工学資源学部, 教授 (50005948)
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| Co-Investigator(Kenkyū-buntansha) |
ASO Setsuo Akita University Faculty of Engineering and Resource Science Associate Professor, 工学資源学部, 助教授 (80167915)
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| Project Period (FY) |
1996 – 1998
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| Keywords | high-temperature alloy / dispersion alloy / Ostwald ripening / precipitation hardened alloy / high-temperature deformation / creep deformation |
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| Research Abstract |
Precipitation hardening has been considered to be an effective strengthening method not only at room temperature but also at high temperatures. Many investigations have been carried out on high temperature deformation of precipitation hardened alloy. Recently, Arzt and Rosier have proposed a model for the high temperature deformation of dispersion strengthened alloys based on an attractive interaction of particle and dislocation, In that model. the rate controlling step in the deformation process is the thermally activated detachment of a dislocation from the departure side of a particle. The dispersion particles are thermal-stable particles. However it is well known that there is Ostwald ripening in precipitation hardened alloy. The precipitates grow up at high-temperature and the dispersion parameters of the precipitates change during high-temperature deformation
In order to clarify the influence of this Ostwald ripening on high-temperature deformation in precipitation hardened alloys, this work proposed a predicting method of high-temperature deformation behavior with Ostwald ripening of precipitates for precipitation hardened alloy. The theoretical calculations were compared with the experimental results for Al-1.03 mass% Si alloy. The evaluation was carried out of the time dependence of the threshold stress, dispersion parameters of Si precipitates and stress-strain curves for Al-1.03 mass% Si alloy. The effects of temperature raging from 473K to 723K on deformation behaviors were calculated by this prediction method. The influence of Ostwald ripening of Si precipitates on high-temperature deformation behaviors was revealed in the Al-Si precipitation hardened alloy, The results were in good agreement with experimental ones.
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