2020 Fiscal Year Final Research Report
initiation and propagation of intergranular stress corrosion cracking
| Project/Area Number |
17H04899
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| Research Category |
Grant-in-Aid for Young Scientists (A)
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| Allocation Type | Single-year Grants |
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| Research Field |
Materials/Mechanics of materials
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| Research Institution | Shizuoka University |
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Principal Investigator |
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| Project Period (FY) |
2017-04-01 – 2021-03-31
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| Keywords | 応力腐食割れ / 粒界 / 応力 / ひずみ / 応力拡大係数 / ステンレス鋼 |
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| Outline of Final Research Achievements |
The present study elucidated the processes of SCC initiation and growth in stainless steels subjected to tension in a corrosive environment to evaluate their SCC life. SCC initiates and grows at grain boundaries (GBs) with high susceptibility to intergranular corrosion. Crack initiation is characterized by normal strain at a GB on the surface of the material, which is caused by stress/strain concentration due to dislocation pile-up near GBs under tensile loading. Crack propagation rate can be formulated using the stress intensity factor K and its gradient dK/da.
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| Free Research Field |
材料強度学
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| Academic Significance and Societal Importance of the Research Achievements |
本研究では，ステンレス鋼に生じるＳＣＣの発生および進展条件を明らかにした．ＳＣＣの発生には，力学および粒界構造に関する条件が必要であり，それらを排除することで耐ＳＣＣ性を有する材料の設計に生かすことが可能である．さらに，ＳＣＣ進展式を提案したことから，高精度な寿命予測が可能となる．これらの結果は，高経年化した機械構造物の健全性確保に資する．
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