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A cooperative Study on Environmentally Assisted Cracking of structural materials of nuclear reactor

Research Project

Project/Area Number 09044117
Research Category

Grant-in-Aid for Scientific Research (B).

Allocation TypeSingle-year Grants
Section一般
Research Field Materials/Mechanics of materials
Research InstitutionTohoku University

Principal Investigator

SHOJI Tetsuo  Graduate School of Engineering, Tohoku University Prof., 大学院・工学研究科, 教授 (80091700)

Co-Investigator(Kenkyū-buntansha) MINKOV DORIAN  Graduate School of Engineering, Tohoku University Ass. Prof., 大学院・工学研究科, 助教授 (30291264)
WATANABE Yutaka  Graduate School of Engineering, Tohoku University Ass. Prof., 大学院・工学研究科, 助教授 (10260415)
SAKA Masumi  Graduate School of Engineering, Tohoku University Prof., 大学院・工学研究科, 教授 (20158918)
NAKAJIMA Mikiko  Graduate School of Engineering, Tohoku University Lec., 大学院・工学研究科, 講師 (80005488)
RAJA KRISHNAN SELVA  Graduate School of Engineering, Tohoku University Res. Ass., 大学院・工学研究科, 助手 (40302179)
ZUBCHENKO Al  ツニトマッシュ研究所, 所長
TIMOFEEV Bor  ロシア構造材料中央研究所, 室長
ZVENZDIN Yur  ロシア連邦工学院, 副学長, 教授
近藤 達男  東北大学, 大学院・工学研究科, 教授 (10271868)
ZVEZDIN Yuri  ロシア連邦工学院, 教授
Project Period (FY) 1997 – 1999
Project Status Completed (Fiscal Year 1999)
Budget Amount *help
¥7,600,000 (Direct Cost: ¥7,600,000)
Fiscal Year 1999: ¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1998: ¥2,700,000 (Direct Cost: ¥2,700,000)
Fiscal Year 1997: ¥3,100,000 (Direct Cost: ¥3,100,000)
KeywordsEnvironmentally Assisted Cracking / Structural materials of Nuclear Reactor / Crack Growth / Nondestructive inspection / Micro Sampling / Water Chemistry / Slip-dissolution Model / き裂先端ひずみ速度 / 表面酸化皮膜 / 電流密度減衰曲線
Research Abstract

Assuring the safety of nuclear power plants is an important issue all over the world. Especially the quantitative evaluation of environmentally assisted cracking (EAC) of materials in high temperature water is critical. However, EAC is affected by so many factors that estimation is not accurate enough up to now.
This is a cooperative research that combines the fundamental research achievements on EAC of the leader of this project with the research results of Russian researchers who possess rich data of practical nuclear reactors. Main achievements can be summarized as follows :
(1) The relation between corrosion fatigue crack growth rate and the shape of MnS inclusions has been studied. It has been shown that the size distribution of the inclusions is more important than the total sulfur content in steel. Reactor pressure vessel steel made by Russian that has high sulfur content but well distributed small particles of MnS inclusions was evaluated in Tohoku University. Results showed that … More the higher crack growth rate expected only from the sulfur content was not observed.
(2) Detection method for small defects have been studied. The validities of induced current focusing potential drop (ICFPD) technique and direct current potential drop (DCPD) technique using adjacent probes were confirmed. A cooperative research project on how to detect inside defects in stainless steel welds from the outer surface has been set up for the future. The materials will be prepared by Central Institute of Structural Materials in Russian. The evaluation will be done in Tohoku University.
(3) The relation between aging degradation of surface film and EAC has been studied. The research results on contact electric resistance and other electric properties accompanying film growth were exchanged. According to the electric property change with film growth during irradiation, the relation to irradiation assisted stress corrosion cracking has been made clearer.
(4) Investigation for improvement for EAC incidents of VVER type nuclear power plants and, strong methods of material test has been done. Defect detection and crack growth rate evaluation have been suggested.
(5) EAC at condensation pail of low pressure seam turbine has been researched. A practical plan about experimental facilities and analysis has been suggested. It has been made clear that Kelvin probe is useful for evaluating corrosion in the thin water layer condition. The experiments have been carried out partly. Less

Report

(4 results)
  • 1999 Annual Research Report   Final Research Report Summary
  • 1998 Annual Research Report
  • 1997 Annual Research Report
  • Research Products

    (51 results)

All Other

All Publications (51 results)

  • [Publications] S.Suzuki,T.Shoji: "SCC Initiation and Propagation Study of SUS 304 in High Temperature Water by ACPD"Proc.of International Symposium on Plant Aging and Life Prediction of Corrodible Structures. 379-388 (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] S.Moriya,T.Shoji: "Surface Crack Growth Behavior of Pressure Vessel Steels Oxygenated High Temperature Water"Proc.of International Symposium on plant Aging and Life Prediction of Corrodible Structures. 937-942 (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] S.Inagaki,J.Fukakura,M.Miyazaki,T.Shoji: "Cathodic Protection Technique for Power Plant Condenser Using Numerical Method"Proc.of International Symposium on plant Aging and Life Prediction of Corrodible Structures. 827-834 (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] B.T.Timofeev,V.A.Fedorova: "Plastic Strain Effect on RPV Materials Behavior"The Forth Meeting on Programme of Scientific and Technical Collaboration between Tohoku University-CRISM<<Prometey>>-SSC NPO TSNIT Mash,12-19 April(1998),Sendai,Japan. (in press).

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] A.A.Gorbakony,B.T.Timofeev,V.A.Petrov: "Damage Mechanism of Piping Welded Joints Made from Corrosion Resistant Cr-Ni Steel in the Process of a Prolonged Operation of the Type RBMK Reactor"The Fifth Meeting of Joint Research Programme between RIFT Tohoku University and CRISM<<Prometey>>within JAPAN-RUSSIA Collaboration for 1997-1999,15 May(1998),St.Petersburg,Russia. (in press).

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] M.Saka,S.R.Ahmed: "Material Issue in Design,Manufacturing and operation of Nuclear Power Plants Equipment"Proceedings of the Fifth International Conference,7-14 June,1998,St.Petersburg,Russia. 168-176 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] B.T.Timofeev,G.P.Karzov,A.A.Gorbakony,Yu.K.Nikolaev: "Corrosion and Mechanical Strength of Welded Joints of Downcomers for RBMK Reactors"The Seventh Meeting of Joint Research Programme between RIFT Tohoku University and CRISM<<Prometey>>within JAPAN-RUSSIA Collaboration for 1997-1999,27 Sept.-2 Oct.(1998),Sendai,RIFT Tohoku University. (in press).

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] Y.Lee: "Quantitative Analysis of Environmentally Assisted Crack Tip Chemistry of Reactor Pressure Vessel Steel in High Temperature Water"Proceedings of Eurocorr'98-The European Corrosion Congress,Sept.28-Oct.1,(1998),Utrecht,The Netherlands. CD-ROM (1999)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] B.T.Timofeev: "Welded Joints Corrosion and Mechanical Strength of Piping for RBMK Reactors"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants,October 2,(1998),Sendai,Japan. 1-4 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] I.L.Kharina: "Effect of External Factors Environment Medium on Corrosion Cracking Low Alloy and Autenic Stainless Steels on Slow Strain Rate in High Temperature Water"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants,October 2,(1998),Sendai,Japan. 5-8 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] I.M.Rafalovich: "Effect of the Hole Drilling Technology on Low Cycle Fatigue Resistance of the Steam Generator Collector Steel"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants,October 2,(1998),Sendai,Japan. 9-12 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] E.I.Mamaeva,I.M.Rafalovich,I.L.Kharina,S.A.Skotnikov: "Investigation of the Service Factors Effect on Degradation of PGV-1000 Steam Generator Header Material"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants,October 2,(1998),Sendai,Japan. 19-22 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] Y.Lee,V.Fedorova,T.Shoji: "Study on Corrosion Fatigue Crack Tip Solution Chemistry of 15X2MFA Steels in BWR and PWR Environments"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants,October 2,(1998),Sendai,Japan. 23-26 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] Y.Kaneshima,G.Li,T.Shoji: "SCC Austenitic Steels Simulated for Grain Boundaries of Irradiated 304 Stainless Steel in PWR Primary Water at 325℃"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants,October 2,(1998),Sendai,Japan. 27-30 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] T.Tonozuka,Y.Watanabe,T.Kondo,T.shoji,f.Masuyama: "Sensitization Properties and IGSCC Susceptibility of Ce-Midified Stainless Steels"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants,October 2,(1998),Sendai,Japan. 31-32 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] T.Shoji,T,Sato,K.Raja: "Comparison of Environmentally Assisted Cracking Behavior Obtained by Different Test Method"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants,October 2,(1998),Sendai,Japan. 35-38 (1998)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] 竹田陽一,K.S.Raja,庄子哲雄: "ケルビンプローブによるステンレス鋼の微視的疲労損傷の計測"日本機械学会東北支部第35期総会・講演会講演論文集. 82-83 (2000)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] T.Shoji,K.S.Raja,G.F.Li,Y.J.Lee,A.Brozova: "Critical parameters of Environmentally Assisted Cracking in Nuclear Systems"Proceedings of Corrosion/2000,NACE'sAnnual Conference,26-31 March,(2000),Orlando,Florida,USA,T-2A. (in press).

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] S. Suzuki, T. Shoji: "SCC Initiation and Propagation Study of SUS 304 in High Temperature Water by ACPD"Proc.Of International Symposium on Plant Aging and Life Prediction of Corrodible Structures. 379-388 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] S. Moriya, T. Shoji: "Surface Crack Growth Behavior of Pressure Vessel Steels Oxygenated High Temperature Water"Proc.Of International Symposium on Plant Aging and Life Prediction of Corrodible Structures. 937-942 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] S. Inagaki, J. Fukakura, M. Miyazaki, T. Shoji: "Cathodic Protection Technique for Power Plant Condenser Using Numerical Method"Proc.Of International Symposium on Plant Aging and Life Prediction of Corrodible Structures. 827-834 (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] B. T. Timofeev, V. A. Fedorova: "Plastic Strain Effect on RPV Materials Behavior"The Fourth Meeting on Programme of Scientific and Technical Collaboration between Tohoku University - CRISM≪Prometey≫ - SSC NPO TSNIIT Mash, 12-19 April(1998), Sendai, Japan. (in press).

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] A. A. Gorbakony, B. T. Timofeev, V. A. Petrov: "Damage Mechanism of Piping Welded Joints Made from Corrosion Resistant Cr-Ni Steel in the Process of a Prolonged Operation of the Type RBMK Reactor"The Fifth Meeting of Joint Research Programme Between RIFT Tohoku University and CRISM ≪Prometey≫ within JAPAN-RUSSIA Collaboration for 1997-1999, 15 May(1998), St.Petersburg, Russia. (in press).

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] M. Saka, S. R. Ahmed: "Material Issue in Design, Manufacturing and operation of Nuclear Power Plants Equipment"Proceedings of the Fifth International Conference, 7-14 June(1998), St.Petersburg, Russia. 168-176 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] B. T. Timofeev, G. P. Karzov, A. A. Gorbakony, Yu. K. Nikolaev: "Corrosion and Mechanical Strength of Welded Joints of Downcomers for RBMK Reactors"The Seventh Meeting of Joint Research Programme between RIFT Tohoku University and CRISM≪Prometey≫ within JAPAN-RUSSIA Collaboration for 1997-1999, 27 Sept.-2 Oct.(1998), Sendai, RIFT Tohoku University. (in press).

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] Y. Lee: "Quantitative Analysis of Environmentally Assisted Crack Tip Chemistry of Reactor Pressure Vessel Steel in High Temperature Water"Proceedings of Eurocorr '98 - The European Corrosion Congress, Sept.28 - Oct.1, (1998), Utrecht, The Netherlands. CD-ROM. (1999)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] B. T. Timofeev: "Welded Joints Corrosion and Mechanical Strength of Piping for RBMK Reactors"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants, October 2, (1998), Sendai, Japan. 1-4 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] I. L. Kharina: "Effect of External Factors Environment Medium on Corrosion Cracking Low Alloy and Austenic Stainless Steels on Slow Strain Rate in High Temperature Water"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants, October 2, (1998), Sendai, Japan. 5-8 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] I. M. Rafalovich: "Effect of the Hole Drilling Technology on Low Cycle Fatigue Resistance of the Steam Generator Collector Steel"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants, October 2, (1998), Sendai, Japan. 9-12 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] E. I. Mamaeva, I. M. Rafalovich, I. L. Kharina, S. A. Skotnikov: "Investigation of the Service Factors Effect on Degradation of PGV-1000 Steam Generator Header Material"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants, October 2, (1998), Sendai, Japan. 19-22 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] Y. Lee, V. Fedorova, T. Shoji: "Study on Corrosion Fatigue Crack Tip Solution Chemistry of 15X2MFA Steels in BWR and PWR Environments"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants, October 2, (1998), Sendai, Japan. 23-26 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] Y. Kaneshima, G. Li, T. Shoji: "SCC of Austenitic Steels Simulated for Grain Boundaries of Irradiated 304 Stainless Steel in PWR Primary Water at 325℃"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants, October 2, (1998), Sendai, Japan. 27-30 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] T. Tonozuka, Y. Watanabe, T. Kondo, T. Shoji, F. Masuyama: "Sensitization Properties and IGSCC Susceptibility of Ce-Midified Stainless Steels"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants, October 2, (1998), Sendai, Japan. 31-32 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] T. Shoji, T. Sato, K. Raja: "Comparison of Environmentally Assisted Cracking Behavior Obtained by Different Test Method"Proceedings of Environmentally Assisted Cracking in Nuclear Power Plants, October 2, (1998), Sendai, Japan. 35-38 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] Youichi Takeda, Krishnan Selva Raja, Tetsuo Shoji: "Microscopic Observation of Fatigue Damaged Area in Stainless Steel by Means of Kelvin Probe"Proceedings of 35th JSME Tohoku Branch Conference, (2000). 82-83 (2000)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] T. Shoji, K. S. Raja, G. F. Li, Y. I. Lee, A. Brozova: "Critical Parameters of Environmentally Assisted Cracking in Nuclear Systems"Proceedings of Corrosion/2000, NACE's Annual Conference, 26-31 March, (2000), Orlando, Florida, USA, T-2A. (in press).

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1999 Final Research Report Summary
  • [Publications] T.Sato: "High Sensitivity Inspection of Defects in Welds by Remotely Induced Current Potential Drop Technique"Nondestrucive Characterization of Materials IX,Sydney, Australia, June/July 1999. 107-112 (1999)

    • Related Report
      1999 Annual Research Report
  • [Publications] T.Shoji,Y.Lee,K.S.Raja,G.Li: "Theoretical Prediction of Environmentally Assisted Cracking of Structural Materiatls in LWR Systems-Threshold and Plateau Growth Behavior-"Proceedings of lnternational Conference on Advanced Technology in Experimental Mechanics '99, July 21-24, 1999, Ube, Yamaguchi,Japan. (1999)

    • Related Report
      1999 Annual Research Report
  • [Publications] T.Shoji,K.S.Raja,G.F.Li,Y.J.Lee and Anna Brozova: "Critical parameters of environmentally assisted cracking in nuclear systems"Proceedings of Corrosion/2000, NACE's Annual Conference, 26-31 March 2000, Orlando, Florida, USA, T-2A. (in press).

    • Related Report
      1999 Annual Research Report
  • [Publications] 李 倫柱: "高温高圧水中における軽水炉圧力容器用鋼の環境助長割れ内部環境の計測に関する研究" 材料と環境. 47,12. 783-788 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] Y.Lee: "Quantitative Analysis of Environmentally Assisted Crack Tip Chemistry of Reactor Pressure Vassel Steel in High Temperature Water" Proceedings of Eurocorr '98-The European Corrosion Congress,Sept.28-Oct.1,1998,Utrecht,The Netherlands. (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] 李 倫柱: "高温高圧水中における低合金鋼のき裂内溶液化学の変化に伴う腐食疲労き裂進展応答" (社)腐食防食協会 第45回材料と環境討論会講演習. 285-288 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] Y.Lee: "Study on Corrosion Fatigue Crack Tip Solution Chemistry of 15X2MFASteels in BWR and PWR Environments" Proceedings of International Workshop on Environmentally Assisted Cracking in Nuclear Power Plants,Oct.2,1998,Sendai. 23-27 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] T.Satoh: "Quantitative Prediction of Environmentally Assisted Cracking Based on a Theoretical Model and Computer Simulation" Journal of Nuclear Materials. 258-263. 2054-2058 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] T.Shoji: "Prediction of Environmentallu assisted Cracking Behavior of Structural Material in LWR Systems:" Proceedings of the 1998 ASME/JSME Joint Pressure Vessels and Piping Conference,July 26-30,1998,San Diego,California. 201-205 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] S.Suzuki and T.Shoji: "SCC Initiation and Propagation Study of SUS 304 in High Temperature Water by ACPD" Proc.of International Symposium on Plant Aging and Life Prediction of Corrodible Stuctures. 379-388 (1997)

    • Related Report
      1997 Annual Research Report
  • [Publications] S.Moriya and T.Shoji: "Surface Crack Growth Behavior of Pressure Vessel Steels in Oxygenated High Temperature Water" Proc.of International Symposium on Plant Aging and Life Prediction of Corrodible Stuctures. 937-942 (1997)

    • Related Report
      1997 Annual Research Report
  • [Publications] S.Inagaki, J.Fukakura, M Miyazaki and T.Shoji: "Cathodic Protection Technique for Power Plant Condenser Using Numerical Method" Proc.of International Symposium on Plant Aging and Life Prediction of Corrodible Stuctures. 827-834 (1997)

    • Related Report
      1997 Annual Research Report
  • [Publications] Y.S.Yi and T.Shoji: "Thermal Aging Embrittlement of Cast Duplex Stainless Steels and its Nondestructive Evaluation Aging and Life Prediction of Corrodible" Proc.of International Symposium on Plant Aging and Life Prediction of Corrodible Stuctures. 371-377 (1997)

    • Related Report
      1997 Annual Research Report
  • [Publications] S.Suzuki, T.Shoji and Y.S.Yi: "Mechanistics and Mechanisms of Environmentally Assisted Cracking Formulation of Corrosion Deformation" The 2^<hd> International Conference of Corrosion Deformation Interactions. (in press). (1998)

    • Related Report
      1997 Annual Research Report
  • [Publications] Y.Watanabe, T.Shoji and T.Kondo: "Electrochemical Noise Characteristics of IGSCC in Stailess Steels in Pressurized High-Temperature Water" Corrosion/98. (in press). (1998)

    • Related Report
      1997 Annual Research Report

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Published: 1997-04-01   Modified: 2021-04-07  

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