Effect of rare earth on lattice size and equilibrium hydrogen pressure for AB5-type MmNi3.55Co0.75Al0.30Mn0.40

Daisuke Endo, Kouji Sakaki, Etsuo Akiba

Research output: Contribution to journalArticlepeer-review

12 Citations (Scopus)


We investigated the effect of rare earth in Mm (misch metal) to crystal structure and hydrogenation properties especially lattice size and equilibrium hydrogen pressure in MmNi3.55Co0.75Al0.30Mn0.40 using X-ray diffraction (XRD) and pressure-composition (P-C) isotherms measurements. We successfully prepared the alloys, where Mm was composed of MxLa0.81-xNd0.14Pr0.05 (Mx = Ce0.47, Y0.40, Gd0.25, Tm0.20, Lu0.16). The substitution amount for each alloy was adjusted to appear stoichiometric single phase and to keep the same lattice volume considering atomic radius of each rare earth element. Among these alloys, however, the Ce containing ones studied showed different characteristics in terms of anisotropy of lattice parameters and equilibrium hydrogen pressure to others. All alloys studied showed the same reversible hydrogen content. Significant difference of the enthalpy and entropy of hydride formation have not been observed.

Original languageEnglish
Pages (from-to)215-219
Number of pages5
JournalJournal of Alloys and Compounds
Issue number1-2
Publication statusPublished - Jul 14 2008
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry


Dive into the research topics of 'Effect of rare earth on lattice size and equilibrium hydrogen pressure for AB5-type MmNi3.55Co0.75Al0.30Mn0.40'. Together they form a unique fingerprint.

Cite this