Kyushu University Academic Staff Educational and Research Activities Database
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Masanobu Kubota Last modified date:2017.05.15

Professor / Hydrogen Materials Compatibilty and Fracture (April 2014 - Current), Air Liquide Industrial Chair on Hydrogen Structural Materials and Fracture (Oct. 2010 - March 2014)
Hydrogen Materials Compatibility Division
International Institute for Carbon-Neutral Energy Research


Graduate School
Undergraduate School
Other Organization


E-Mail
Homepage
http://www.mech.kyushu-u.ac.jp/lab/engmat/kondo.html
Our laboratory’s activities which are not only academic but also daily life are introduced. .
Phone
092-802-6720
Academic Degree
Dr. Eng
Field of Specialization
Strength of engineering materials, Metal fatigue, Fretting fatigue, Hydrogen structural materials
Outline Activities
Experiment-based studies on the effects of hydrogen on strength of materials are being carried out in the Hydrogen Materials Compatibility Research Division at the Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University. Particularly for fatigue e limit in high-pressure hydrogen is studying at the Research Center for Hydrogen Industrial Use and Storage (HYDROGENIUS). The studies are doing with the students from the Department of Mechanical Engineering by the help of the Department.

Education: I am in charge of Academic frontier for all undergraduate students, Advanced engineering for international course students, mechanical engineering experiment for 3rd grade student in mechanical engineering course, and hydrogen structural material for master course students in mechanic al engineering. For graduation thesis, I am aiming at not only cutting-edge research but also that students will be able to manage independently. There the students will learn knowledges about strength of material as well as programing, electric circuit, machining, design, drawing, presentation and so on. For the improvement of my teaching skills, I attend to faculty development courses and join to Japanese Society for Engineering Education.

Research: Metal fatigue is the major subject of my researches. Particularly, fretting fatigue is my lifetime work. At present, I put the most effort into the research on the effects of hydrogen on material strength.
(1) Effect of hydrogen on fretting fatigue, fatigue and fracture toughness: To achieve optimization of cost and performance of high-pressure hydrogen containment systems without compromising safety, these studies are being carried out.

(2) Fatigue limit in high-pressure hydrogen gas: We developed a special fatigue testing machine to obtain fatigue limit in high-pressure hydrogen. We have many strong request for such data from industry and the government.

(3) Material issues in next-generation hydrogen utilization systems: It can be expected that SOFC and SOEC will be extensively used in the near future. Therefore, material strength in hydrogen at elevated temperature must be investigated.

(4) Crack initiation in fretting fatigue: Fretting fatigue is one of the major factors in the design of machines and structure to prevent catastrophic failure accidents. Mechanism and the method how to evaluate quantitatively are studying with a company.

Social contribution: Steering committee of Kyushu branch of the Japan Society of Materials Science (2008-2015), Editorial committee of journal of Japan Society for Mechanical Engineers (2009-2010), Referee of contributed paper to JSME journal (domestic and international), International symposium (MMYoung and ISFF), Workshops, Board member of the Japan Society of Materials Science (2016-)

International cooperation: Local committee (Asia region) of International symposium on fretting fatigue (ISFF 6- 8), Planning committee of international symposium for young researchers (M&M div, JSME)
Research
Research Interests
  • Development of weld joint for high-pressure hydrogen piping
    keyword : Hydrogen, Welding technique
    2014.04~2017.03.
  • Fatigue limit in high-pressure hydrogen
    keyword : Hydrogen, Fatigue Limit
    2014.04~2018.03.
  • Degradation of material strength in hydrogen at elevated temperature
    keyword : Hydrogen, High temperature, Creep, Fatigue
    2017.04~2019.03.
  • Inhibitory effect on hydrogen-assisted degradation of material strength
    keyword : Hydrogen, Fracture, Fatigue, Fretting, Impurity
    2014.04~2018.03.
  • study on propagation behavior of small crack in railway wheel materials
    keyword : Small crack, Crack propagation, Threshold, Railway
    2010.04.
  • Effect of hydrogen on fracture toughness
    keyword : Hydrogen Fracture toughness
    2010.10~2013.09.
  • Evaluation of fretting fatigue strength of mechanical component received torsion
    keyword : Fretting fatigue, Torsion, Spline, Press Fit
    2008.04Evaluation and improvement of fretting fatigue strength in machine component applied cyclic torsion.
  • Elucidation of mechanism of fretting fatigue strength reduction due to hydrogen
    keyword : Hydrogen, Fretting Fatigue, Mechanism, Reduction of Fretting Fatigue strength, Adhesion, Small cracks
    2007.04Mechanism elucidation of fretting fatigue strength reduction due to hydrogen gas: Fretting fatigue strength decreases in hydrogen gas environment. To clarify the mechanisms, elaborate observations of fretted surface and crack propagation behavior are doing. .
  • Effect of hydrogen gas and absorbed hydrogen on fretting fatigue strength
    keyword : Hydrogen gas, Hydrogen concentration, Fretting fatigue strength
    2003.04The objective of this study is to clarify the effect of hydrogen gas on fretting fatigue strength of the materials used for hydrogen utilization machines and structures. In hydrogen gas environment, fretting fatigue strengths of A286, SUS304 and SUS316L decrease in the long-life region..
  • Selection of shape and size of stress-relief groove for improvement of fretting fatigue strenth
    keyword : Fretting fatigue, Stress-relief groove, Improvement of fretting fatigue strength
    2005.04Stress relief groove has been used to improve the fretting fatigue strength of fitted part between mechanical components. However, the applicability of groove has not been fully evaluated and there are insufficient investigations to determine the optimal groove shape. In this study, the evaluation of fretting fatigue strength of specimens which have various shapes of stress relief groove was conducted by fretting fatigue tests and FEM analyses in order to develop an index for the selection of groove shape..
Current and Past Project
  • Introduction of nitrogen stainless steel and its weld joint is required for high-pressure hydrogen piping. Nitrogen is important alloying element to improve strength and hydrogen compatibility, however, the state of existence may be changed during welding process. This study is aiming at development of weld joint of nitrogen stainless steel which is applicable for high-pressure hydrogen piping. ①Development of welding technique, ②Characterization of microstructure, ③Study on hydrogen compatibility of developed weld joint.
  • ・Study on hydrogen compatibility of engineering steels and alloys
    ・Study on hydrogen compatibility of specific materials to expand allowable pressure range and temperature range
    ・Provision of hydrogen materials data sheets
  • To secure sustainable development of humankind, early realization of low-carbon economy and hydrogen society is necessary. Development of wide range of technologies is indispensable.
  • Comprehensive tie-up between Kyushu University and Hitachi Ltd. Investigations of fatigue strength under high-pressurized hydrogen environment
  • Development of fatigue strength design method for hydrogen utilization machines
  • Development for safe utilization and infrastructure of hydrogen project
  • Integration Technology of Mechanical System for Hydrogen Utilization
Academic Activities
Reports
1. Contact Mechanics and Evaluation of Fretting Fatigue Strength.
2. Contact Mechanics and Evaluation of Fretting Fatigue Strength.
Papers
1. 久保田 祐信, 片岡 俊介, 髙﨑 大裕, 近藤 良之, A Quantitative Approach to Evaluate Fretting Fatigue Limit Using a Pre-Cracked Specimen, Tribology International, 108, 2017.04.
2. 久保田 祐信, 薦田 亮介, Jader Furtado, Fretting fatigue in hydrogen and the effect of oxygen impurity, Proc. the Asian Conference on Experimental Mechanics 2016 (ACEM 2016), 2016.11.
3. Fatigue properties of work-hardened oxygen-free cupper in high-pressure hydrogen.
4. Fundamental Mechanisms Causing Reduction in Fretting Fatigue Strength by Hydrogen
(Effect of Hydrogen on Small Crack Initiation at the Adhered Spot).
5. Fundamental Mechanisms Causing Reduction in Fretting Fatigue Strength by Hydrogen
(Effect of Hydrogen on Small Crack Initiation at the Adhered Spot).
6. "Effects of Multiple Overloads and Hydrogen on High-Cycle Fatigue Strength of Notched Specimen of Austenitic Stainless Steels" in the transactions of the Japan Society for Mechanical Engineers, Ser. A.
7. Kanetaka MIYAZAWA, Masato MIWA, Akihiro TASHIRO, Tatsuro AOKI Masanobu KUBOTA and Yoshiyuki KONDO, Improvement of Torsional Fretting Fatigue Strength of Splined Shaft Used for Car Air Conditioning Compressors by Hybrid Joint, Journal of Solid Mechanics and Materials Engineering, 5, 12, 753-764, 2011.12.
8. Mechanism of reductin of fretting fatigue limit in hydrogen gas in SUS304.
9. Masanobu Kubota, Tsuyoshi Nishimura, Yoshiyuki Kondo, Effect of hydrogen concetration on fretting fatigue strength, Journal of solid mechanics and material engineering, 4, 6, 816-829, 2010.06.
10. Masanobu KUBOTA, Shunsuke KATAOKA and Yoshiyuki KONDO, Effect of Stress Relief Groove on Fretting Fatigue Strength and Index for the Selection of Optimal Groove Shape, International Journal of fatigue, 31, 3, 439-446, 2010.05.
11. Masanobu KUBOTA, kenj HIRAKAWA, The effect of rubber contact on the fretting fatiguestrength of railway wheel tire, Tribology International, 42, 9, 1352-1359, 2010.05.
12. Masanobu KUBOTA, Yasuhiro TANAKA, Kyohei KUWADA and Yoshiyuki KONDO, Hydrogen Gas Effect on Fretting Fatigue Properties of Materials Used in Hydrogen Utilization Machines, Tribology International, 42, 9, 1352-1359, 2010.05.
13. Masanobu Kubota, Kenji Hirakawa, The effect of rubber contact on the fretting fatigue strength of railway wheel tire, Tribology International, Vol. 42, pp.1389-1398, 2009.09.
14. Masanobu Kubota, Yasuhiro Tanaka, Yoshiyuki Kondo, The effect of hydrogen gas environment on fretting fatigue strength of materials used for hydrogen utilization machines, Tribology International, Vol. 42, pp. 1352-1359, 2009.09.
15. Masanobu KUBOTA, Yasuhiro TANAKA and Yoshiyuki.KONDO, Fretting Fatigue Strength of SCM435H Steel and SUH660 Heat Resistant Steel in Hydrogen Gas Environment, Tribotest, Vol. 14, pp.177-191, 2008.09.
16. Masanobu KUBOTA, Yasuhiro TANAKA, Kyouhei KUWADA and Yoshiyuki KONDO, Mechanism of Reduction of Fretting Fatigue Limit in Hydrogen Gas Environment, Proceedings of the 3rd International Conference on Material and Processing, Distributed by CD-ROM, 2008.09.
17. Masanobu KUBOTA, Shunsuke KATAOKA and Yoshiyuki KONDO, Effect of Stress Relief Groove on Fretting Fatigue Strength and Index for the Selection of Optimal Groove Shape, International Journal of Fatigue, Vol. 31, pp.436-446, 2008.07.
18. Fretting Fatigue Properties of SCM435H and SUH660 in Hydrogen Gas Environment by Masanobu KUBOTA, Yasuhiro TANAKA and Yoshiyuki KONDO, Transactions of Japan Society of Mechanical Engineers, Vol .73, No. 736, pp. 1382-1387 (2007.12)
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19. Shunsuke Kataoka, Chu Sakae, Masanobu Kubota, Yoshiyuki Kondo, Effect of Stress Relief Groove Shape on Fretting Fatigue Strength, Key Engineering Materials, Vol.353-358, 2007, pp.856-859, 2007.11.
20. Masanobu Kubota, Shunsuke Kataoka, Yoshiyuki Kondo, Evaluation of optimal shape of stress relief groove for the improvement of fretting fatigue strength , Proceedings of ATEM07, Distributed by CD-ROM, 2007.09.
21. M. Kubota, N. Noyama, C. Sakae and Y. Kondo, Fretting in Hydrogen gas, Tribology international, 39/10, pp.1241-1247, 2006.10.
22. Effect of hydrogen gas environment on fretting fatigue strength.
23. Masanobu KUBOTA, Sotaro NIHO, Chu SAKAE and Yoshiyuki KONDO, Effect of Under Stress on Fretting Fatigue Crack Initiation of Press-Fitted Axle, JSME International Journal, 46, 3, Vol. 46, No. 3, pp.297-302, 2003.07.
24. Masanobu KUBOTA, Hidenori ODANAKA, Chu SAKAE, Yoshihiro OHKOMORI, and Yoshiyuki KONDO, The Analysis of Fretting Fatigue Failure in Backup Roll and its Prevention, ASTM STP 1425, 1425, pp. 434-445, 2003.03.
25. Masanobu Kubota, Sotaro Niho, Chu Sakae and Yoshiyuki Kondo, Effect of Under Stress on Fretting Fatigue Crack Initiation of Press-Fitted Axle, Proc. of JSME/ASME International Conference on Materials and Processing 2002, 46, 3, Proc. of JSME/ASME International Conference on Materials and Processing 2002, 2002.10.
26. Masanobu KUBOTA, Kentaro TSUTSUI, Taizo MAKINO, Kenji HIRAKAWA, The Effect of the Contact Conditions and Surface Treatments on the Fretting Fatigue Strength of Medium Carbon Steel, ASTM STP 1367, 1367, 2000.01.
27. M. Kubota, T. Ochi, A. Ishii and R. Shibata, Crack Propagation Properties on HIP-Treated Cast Aluminum Alloys, Material Science and Research International, 4, 3, Vol. 4, No. 3, pp. 193-199, 1998.09.
Presentations
1. 久保田 祐信, MACADRE ARNAUD PAUL ALAIN, Hydrogen Compatibility of Ultra-Fine Grain Austenitic Stainless Steel, International Colloquium on Environmentally Preferred Advanced Generation Grid evolution global summit "HYDROGEN" (ICEPAG2017), 2017.03.29.
2. 久保田 祐信, 薦田 亮介, Jader Furtado, Fretting fatigue in hydrogen and the effect of oxygen impurity, The 15th Asian Coference on Experimental Mechanics (ACEM2016), 2016.11.15.
3. 髙﨑 大裕, 久保田 祐信, 薦田 亮介, 吉田 修一, 奥 洋介, 牧野 泰三, 杉野 正明, Effect of Contact Pressure on Fretting Fatigue Failure of Oil-Well Pipe Material
, The 15th Asian Coference on Experimental Mechanics (ACEM2016), 2016.11.15.
4. 久保田 祐信, Akihide Nagao, University of Illinois at Urbana Champaign, Harvard University, University of Illinois at Urbana Champaign, University of Thessaly, Sandia National Laboratories, Livermore, SOFRONIS PETROS, Constitutive equations of hydrogen-enhanced plasticity for quantitative understanding of the mechanisms of hydrogen-assisted fracture, 2016 International Hydrogen Conference, 2016.09.14.
5. 久保田 祐信, 薦田 亮介, Jader Furtado, The effect of oxygen impurities on fretting fatigue of austenitic stainless steel in hydrogen gas, 2016 International Hydrogen Conference, 2016.09.12.
6. 久保田 祐信, 片岡 俊介, 近藤 良之, A quantitative approach to evaluate fretting fatigue limit using a pre-cracked specimen, 8th International Symposium on Fretting Fatigue (ISFF8), 2016.04.18.
7. 久保田 祐信, 森 功一, MACADRE ARNAUD PAUL ALAIN, Study on Hydrogen Compatibility in Fatigue of Ultra-Fine Grain Austenitic Stainless Steel, European Congress and Exhibition on Advanced Mterials and Processes 20415 (EUROMAT 2015), 2015.09.23.
8. 久保田 祐信, 薦田 亮介, Jader Furtado, Basic Study on The Effect of Hydrogen on Fretting Fatigue, Society of Tribologists and Lubrication Engineers (STLE), 2014 Annual Meeting at Disney Contemporary Resort, 2014.05.20.
9. Factors affect fretting fatigue propertoes in hydrogn.
10. 久保田 祐信, Jader Furtado, 薦田 亮介, 吉開 巨都, Fretting fatigue properties under the effect of hydrogen and the mechanisms that cause the reduction in fretting fatigue strength, Joint HYDROGENIUS & I²CNER International Workshop on Hydrogen-Materials Interactions, 2014.01.31.
11. 久保田 祐信, High-cycle fatigue properties of work-hardened copper in 10MPa hydrogen gas, Joint HYDROGENIUS & I²CNER International Workshop on Hydrogen-Materials Interactions, 2014.01.31.
12. Fatigue properties of ultra-fine grain austenitic stainless steel and effect of hydrogen.
13. Jader Furtado, 薦田亮介, 久保田 祐信, Fretting fatigue properties under the effect of hydrogen and the mechanisms that cause the reduction in fretting fatigue strength, 13th International Conference on Fracture (ICF-13), 2013.06.19.
14. 宮澤金敬, 三輪昌人, 近藤 良之, 久保田 祐信, DEVELOPMENT OF THE HYBRID JOINT AND TORSIONAL FRETTING FATIGUE STRENGTH IMPROVEMENT IN THE POWER TRANSMISSION SHAFT, Seventh International Symposium on Fretting Fatigue, 2013.04.10.
15. 久保田 祐信, 薦田亮介, 足立裕太郎, 近藤 良之, Jader Furtado, EFFECT OF HYDROGEN AND IMPURITIES ON FRETTING FATIGUE PROPERTIES
, Seventh International Symposium on Fretting Fatigue, 2013.04.09.
16. 薦田亮介, 久保田 祐信, 近藤 良之, Jader Furtado, THE MECHANISM CAUSING REDUCTION IN FRETTING FATIGUE STRENGTH DUE TO HYDROGEN, Seventh International Symposium on Fretting Fatigue, 2013.04.09.
17. A study on the damage caused by repetitive open-close movement in a high-pressure hydrogen gas valve.
18. Effects of Multiple Overloads and Hydrogen on High-Cycle Fatigue Strength of Notched Specimen of Austenitic Stainless Steel and Prediction of Reduction of Fatigue Limit
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19. Effects of Notch Root Radius and Stress Ratio on the Behavior of Short Crack at Notch Root.
20. Effect of 10MPa Hydrogen gas environment on high-cycle fatigue properties of carbon steels.
21. "Effect of Hydrogen on Fretting Fatigue Strength of SUS316L Austenitic Stainless Steel" presented at JSME Kyushu branch annual technical meeting 2011 took place in Ito campus, Kyushu University.
22. Effectiveness of combination of press-fit for improvement of fatigue strength of splined shaft.
23. Effect of Hydrogen on Fretting Fatigue in Austenitic Stainless Steels.
24. Improvement of Fretting Fatigue Strength by Hybrid Joint.
25. Mechanism of Reduction of Fretting Fatigue Limit in Hydrogen Gas in SUS304.
26. Optimization of Shape of Stress-relief Groove for Improvement of Fretting Fatigue Strength.
27. Effect of Hydrogen on the Reduction of Fatigue Strength by Multiple Overloading.
28. Mechanism of Reduction of Fretting Fatigue Limit in Hydrogen Gas Environmet.
29. Contact Mechanics and Evaluation of Fretting Fatigue Strength .
30. The effect of hydrogen gas environment on fretting fatigue strength of materials used for hydrogen utilization machines
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31. Fretting and Fatigue.
32. Evaluation of Fretting Fatigue Strength and Fatigue Design Method.
33. The effect of hydrogen gas environment on fretting fatigue strength of materials used for hydrogen utilization machines
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34. Fretting and Fatigue
Masanobu Kubota.
35. Fretting fatigue and Design Method
Masanobu Kubota.
36. Effect and Elucidation of Mechanism of Hydrogen Gas Environment on Fretting Fatigue Strength of Hydrogen Utilization Machines’ materials.
37. Evaluation of Fatigue Strength of Fine Copper Wire for Electric Equipment
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Awards
  • Development of environmental-friendly and energy-saving car air-conditioning compressor using downsized power transmission shaft by hybrid joint structure
  • Mechanism of Reduction of Fretting Fatigue Limit in Hydrogen Gas in SUS304
  • Award for the Best Paper 2007, Japan Society of Materials Science
    Effect of stress relief groove shape on fretting fatigue strength and index for the selection of groove shape
  • Studies on effect of influence factors on fretting fatigue and quantitative evaluation of fretting fatigue strength
Educational
Social
Professional and Outreach Activities
Many collaborations with industry in terms of analysis and prevention of failure caused by fatigue, fretting fatigue and hydrogen embrittlement were done. Usually failure accident is hidden by the sense of company secret, but in two cases, publications in scientific journal were made. The results of my research were taken into account in some lawsuits as an expert opinion.

For the contribution to regional industry, some collaborative researches were done with small companies in Kyushu area.

I believe that development of real products is the highest goal of our study (Technology transfer). It is very important in terms of relevance of studies.

I served as a board member, journal editors committee, reviewer, managing committee in academic societies. I try to do my best to further development of academic societies.

I held many seminars for citizens, high-school students and engineers in order to educate importance of fatigue, fretting fatigue and hydrogen embrittlement.
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