Phase Diagram and Superabundant Vacancy Formation in Cr-H Alloys

• Fukai Yuh

  Department of Physics, Chuo University

• Mizutani Masaki

  Department of Physics, Chuo University

抄録

X-ray diffraction measurements on the Cr–H system were made using synchrotron radiation at high hydrogen pressures and high temperatures, and the phase diagram was determined up to p(H₂)=5.5 GPa and T\\lesssim1400 K. Three solid phases were found to exist; a bcc phase (α) of low hydrogen concentrations, x=[H]⁄[Cr]\\lesssim0.03 existing at low hydrogen pressures (\\lesssim4.4 GPa), and two high-pressure phases, an hcp (ε) phase at lower temperatures and an fcc (γ) phase at higher temperatures, both having high hydrogen concentrations x∼1. A drastic reduction of the melting point is caused by dissolution of hydrogen. A gradual lattice contraction observed in the fcc phase indicates the formation of superabundant Cr-atom vacancies (vacancy-hydrogen clusters). Thermal desorption measurements after recovery from high p(H₂), T treatments revealed several desorption stages including those due to the release from vacancy-hydrogen clusters and from hydrogen-gas bubbles, and allowed determination of relevant trapping energies.

収録刊行物

• MATERIALS TRANSACTIONS

  MATERIALS TRANSACTIONS 43 (5), 1079-1084, 2002

  公益社団法人 日本金属学会

キーワード

• chromium
• hydrogen
• phase diagram
• superabundant vacancy
• high pressure
• X-ray diffraction

詳細情報

• CRID: 1390001204247785600
• NII論文ID: 10012323457
• NII書誌ID: AA1151294X
• DOI: 10.2320/matertrans.43.1079
• COI: 1:CAS:528:DC%2BD38Xlt1entbg%3D
• ISSN: 13475320
• ISSN: 13459678
• ISSN: http://id.crossref.org/issn/09161821
• NDL書誌ID: 6180205
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I6180205
• Web Site: https://www.jstage.jst.go.jp/article/matertrans/43/5/43_5_1079/_pdf
• 本文言語コード: en
• データソース種別:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可