Development of High Performance Mg2Ni Hydrogen Storage Alloy with Nano-Grained Structure

2016 Fiscal Year Annual Research Report

• Project/Area Number: 15K14183
• Research Institution: Kyushu University
• Principal Investigator: 堀田 善治 九州大学, 工学研究院, 教授 (20173643)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 巨大ひずみ / 高圧ねじり加工 / Mg合金 / 水素結合エネルギー / 水素貯蔵合金 / 格子欠陥 / 積層欠陥

Outline of Annual Research Achievements

初年度は、高圧下でのねじり加工（HPT加工）を利用してMg2Niに大量ひずみを導入し、水素圧力組成等温測定装置(PCI)にて水素吸脱特性を評価した。比較のために、HPT加工を施していない焼鈍材やHPT加工後に焼鈍を施した試料においても同様の測定を行った。組織観察や構造解析にはX線回折、走査電子顕微鏡、透過電子顕微鏡を用い、水素吸脱特性との相関を調べた。HPT試料では結晶粒はナノレベルに微細化し423 Kの温度でも3.3wt%の水素を初期活性化なしで吸蔵した。結晶粒界は水素の高速移動に有効であることが分かった。HPT加工後に焼鈍した試料では結晶粒がミクロンレベルに粗大化するにもかかわらず、HPT試料と同様に水素の吸収が起こった。高分解能電子顕微鏡観察によれば、積層欠陥が多数生じていて、水素の高速拡散経路になったものと判断した。Mg2Ni以外にも、Mg2TiやMgZrの化合物もHPT加工を行い結晶粒がナノ化することを確認した。特にMgZrは室温で吸蔵速度が速くなることを確認した。
２年度目（最終年度）は、水素化し易い元素と水素放出を速める元素を適宜混合し水素結合エネルギーが全体でゼロになる状態にする、いわゆるBinding Energy Engineering のもとに研究を進めた。代表的な組成としてMg4NiPd とMg4NiSnを選択し、HPT加工で多量の格子欠陥を導入し原子オーダでの混合を図った。X線回折、走査電子顕微鏡、透過電子顕微鏡を用い、前者ではbcc構造に変態し、後者ではアモルファス構造に変化することを観察した。また、それぞれにおいて水素吸脱特性を評価し、 Mg4NiPdでは1.3%の水素が、Mg4NiSnでは0.4%の水素が吸蔵できることを確認した。

Research Products

• [Journal Article] Hydrogen Diffusion in Ultrafine-Grained Iron with the body-centered cubic crystal structure (2017)
  • Author(s): H. Iwaoka, M. Arita, Z. Horita
  • Journal Title: Philosophical Magazine Letters Volume: 97 Pages: 158-168
  • DOI: http://dx.doi.org/10.1080/09500839.2017.1300702
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Hydrogen generation from pure water using Al-Sn powders consolidated through high-pressure torsion (2016)
  • Author(s): F. Zhang, R. Yonemoto, M. Arita, Z. Horita
  • Journal Title: Journal of Materials Reseach Volume: 31 Pages: 775-782
  • DOI: https://doi.org/10.1557/jmr.2016.74
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Activation of titanium-vanadium alloy for hydrogen storage by introduction of nanograins and edge dislocations using high-pressure torsion (2016)
  • Author(s): K. Edalati, H. Shao, H. Emami, H. Iwaoka, E. Akiba, Z. Horita
  • Journal Title: International Journal of Hydrogen Energy Volume: 41 Pages: 8917-8924
  • DOI: http://dx.doi.org/10.1016/j.ijhydene.2016.03.146
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Impact of severe plastic deformation on microstructure and hydrogen storage of titanium-iron-manganese intermetallics (2016)
  • Author(s): K. Edalati, M.. Matsuo, H. Emami, S. Itano, A. Alhamid, A. Staykov, D. J. Smith, S. Orimo, E. Akiba, Z. Horita
  • Journal Title: Scripta Materialia Volume: 124 Pages: 108-111
  • DOI: http://dx.doi.org/10.1016/j.scriptamat.2016.07.007
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Scaling up of High-Pressure Sliding (HPS) for Grain Refinement and Superplasticity (2016)
  • Author(s): Y. Takizawa, T. Masuda, K. Fujimitsu, T. Kajita, K. Watanabe, M. Yumoto, Y. Otagiri, Z. Horita
  • Journal Title: Metallurgical and Materials Transactions A Volume: 47 Pages: 4669-4681
  • DOI: 10.1007/s11661-016-3623-3
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Plastic Strain and Grain Size Effect on Phase Transformations in TiO2 Ceramics Processed by high-pressure Torsion (2016)
  • Author(s): H. Razavi-Khosroshahi, K. Edalati, M. Arita, Z. Horita, M. Fuji
  • Journal Title: Scripta Materialia Volume: 124 Pages: 59-62
  • DOI: http://dx.doi.org/10.1016/j.scriptamat.2016.06.022
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Visible-Light-Driven Photocatalytic Hydrogen Generation on Nanosized TiO2-II Stabilized by High-Pressure Torsion (2016)
  • Author(s): H.Razavi-Khosroshahi, K. Edalati, M. Hirayama, H. Emami, M. Arita, M. Yamauchi, S. Ida, T. Ishihara, E. Akiba, Z. Horita, M. Fuji
  • Journal Title: ACS Catalysis Volume: 4 Pages: 5103-5107
  • DOI: 10.1021/acscatal.6b01482
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Presentation] Upsizing of Severe Plastic Deformation Process under High Pressure (2017)
  • Author(s): Zenji Horita
  • Organizer: 7th Latin American Conference on Metastable and Nanostructured Materials (NANOMAT 2017)
  • Place of Presentation: Brotas, SP, Brazil
  • Year and Date: 2017-03-19 – 2017-03-22
  • Int'l Joint Research / Invited
• [Presentation] 巨大ひずみ加工による多機能性合金の開発 (2017)
  • Author(s): 堀田善治
  • Organizer: 日本金属学会２０１７年春期（第１６０回)講演大会
  • Place of Presentation: 首都大学東京南大沢キャンパス
  • Year and Date: 2017-03-15 – 2017-03-17
  • Invited
• [Presentation] Severe Plastic Deformation under High Pressure: Scaling-up of high-pressure sliding for grain refinement and enhanced mechanical properties (2016)
  • Author(s): Yoichi Takizawa, Takahiro Masuda, Kazushige Fujimitsu, Takahiro Kajita, Kyohei Watanabe, Manabu Yumoto, Yoshiharu Odagiri, Zenji Horita
  • Organizer: Engineering Mechanics Institute Conference (2016EMI-IC)
  • Place of Presentation: Metz, France
  • Year and Date: 2016-10-25 – 2016-10-27
  • Int'l Joint Research / Invited
• [Presentation] Production of high-performance hydrogen storage materials using process of severe plastic deformation under high pressure (2016)
  • Author(s): Zenji Horita
  • Organizer: 9 th NATIONAL SEMINAR OF METALLURGY AND MATERIALS (SENAMM IX)
  • Place of Presentation: University of Sultan Ageng Tirtayasa, Indonesia.
  • Year and Date: 2016-10-11 – 2016-10-11
  • Int'l Joint Research / Invited
• [Presentation] 巨大ひずみ加工による材料改質と高性能化に関する研究 (2016)
  • Author(s): 堀田善治
  • Organizer: 日本金属学会２０１６年秋期（第１５９回)講演大会
  • Place of Presentation: 大阪大学豊中キャンパス
  • Year and Date: 2016-09-21 – 2016-09-23
  • Invited
• [Presentation] Role of Grain Boundary for Hydrogen Diffusion in FCC-Pd and BCC-Fe (2016)
  • Author(s): Hideaki Iwaoka, Makoto Arita, Zenji Horita
  • Organizer: 2016 International Hydrogen Conference
  • Place of Presentation: Grand Teton Lodge, Moran, WY, USA
  • Year and Date: 2016-09-11 – 2016-09-14
  • Int'l Joint Research
• [Presentation] 巨大ひずみ加工を利用した材料組織制御と高機能化 (2016)
  • Author(s): 堀田善治
  • Organizer: SPring-8シンポジウム2016
  • Place of Presentation: 関西学院大学 神戸三田キャンパス
  • Year and Date: 2016-08-29 – 2016-08-29
  • Int'l Joint Research / Invited
• [Presentation] Scaling up of high-pressure torsion and production of superplastic Mg alloys (2016)
  • Author(s): Takahiro Masuda and Zenji Horita
  • Organizer: The 9th Pacific Rim International Conference on Advanced Materials and Processing (PRICM-9)
  • Place of Presentation: Kyoto International Conference Center
  • Year and Date: 2016-08-01 – 2016-08-05
  • Int'l Joint Research
• [Presentation] Hydrogen storage performance of TiFe-based compounds processed by HPT (2016)
  • Author(s): Kaveh EDALATI, Motoaki MATSUO, Hoda EMAMI, Shota ITANO, Ali ALHAMIDI, Aleksandar STAYKOV, David J. SMITH, Shin-ichi ORIMO, Etsuo AKIBA, Zenji HORITA
  • Organizer: The 9th Pacific Rim International Conference on Advanced Materials and Processing (PRICM-9)
  • Place of Presentation: Kyoto International Conference Center
  • Year and Date: 2016-08-01 – 2016-08-05
  • Int'l Joint Research
• [Presentation] Severe plastic deformation under high pressure for enhanced mechanical and functional properties (2016)
  • Author(s): Zenji Horita
  • Organizer: 2016 Nanomaterials Workshop
  • Place of Presentation: Nanjing University of Science and Technology, Nanjing, China
  • Year and Date: 2016-06-06 – 2016-06-08
  • Int'l Joint Research / Invited
• [Presentation] Hydrogen storage materials for energy saving and low CO2 emission: microstructural refinement by HPT for high performance (2016)
  • Author(s): Zenji Horita
  • Organizer: International Symposium, Energies marines
  • Place of Presentation: Caen, France
  • Year and Date: 2016-05-12 – 2016-05-12
  • Int'l Joint Research / Invited
• [Book] Promoting Functionality by Severe Plastic Deformation Significance of Lattice Defects and Phase Transformation (2016)
  • Author(s): Kaveh Edalati, Yoshifumi Ikoma and Zenji Horita
  • Total Pages: 80
  • Publisher: IRC-GSAM, Kyushu University
• [Remarks] 堀田研究室ホームページ
  • URL: http://zaiko6.zaiko.kyushu-u.ac.jp/
• [Remarks] 九州大学巨大ひずみマテリアル国際研究センター
  • URL: http://irc-gsam.kyushu-u.ac.jp/
• [Funded Workshop] International Workshop on Giant Straining Process for Advanced Materials in 2016 (GSAM2016) (2016)
  • Place of Presentation: Dai-hakata Bldg. Room 1107, Fukuoka
  • Year and Date: 2016-07-28 – 2016-07-31