Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1625910 | Journal of Alloys and Compounds | 2007 | 5 Pages |
Abstract
Partially Mg-substituted Ca2Si alloys (Ca2−xMgxSi, 0 ≤ x ≤ 1) were synthesized via high-temperature evacuation of CaH2/MgH2/Si ball-milled mixtures. Neutron diffraction refinements showed that Ca2−xMgxSi (0 < x < 1) samples are not single-phase solid-solutions, but rather (1−x)Ca2Si + xCaMgSi mixed phases. Hydrogen absorption measurements indicated that, although pure Ca2Si (x = 0) is readily hydridable and forms an unusual amorphous-hydride phase, pure CaMgSi (x = 1) does not noticeably absorb hydrogen up to 7 MPa H2 and 473–573 K. Thus, hydrogen absorption behaviors of the intermediate compositions (0 < x < 1) are dominated by the Ca2Si component, as evidenced by the isotherm measurements and neutron vibrational spectra.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Hui Wu, Wei Zhou, Terrence J. Udovic, John J. Rush,