The phase relations and hydrogenation behavior of Sr1-xCaxAl2 (x=0, 0.1, 0.2, 0.3, 0.5, 0.75 and 1.0) alloys have been studied. It was found that the Zintl phase with orthorhombic structure existed when x≤0.1, which transformed into an unknown hydride phase under hydrogen pressure of 7 MPa at 543 K for 5 days. Increasing x to 0.2, the Zintl phase and C15-type Laves phase coexisted. Both of them transformed into (Sr,Ca)H2 and Al upon hydrogenation. When x≥0.3, however, there was no Zintl phase but the Laves phase was dominant. After hydrogenation, there a certain amount of (Sr,Ca)H2 and Al as well as a large amount of C15 phase remained in hydrogenated Sr0.7Ca0.3Al2, Sr0.5Ca0.5Al2 and Sr0.25Ca0.75Al2. The crystal structure of the binary CaAl2 alloy did not change with hydrogenation.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry