Pressure dependence of hydrogen-induced amorphization in C15 Laves phase ErFe2

✍ Scribed by K. Aoki; M. Dilixiati; K. Ishikawa

• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 362 KB
• Volume: 375-377
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/j.msea.2003.10.028

✦ Synopsis

C15 Laves phase ErFe 2 was thermally analyzed using a pressure differential scanning calorimeter (PDSC) in a hydrogen atmosphere. Hydrogen absorption in a crystalline state, hydrogen-induced amorphization (HIA), precipitation of ErH 2 in the amorphous phase and decomposition of the remaining amorphous phase into ␣-Fe and ErH 2 occurred exothermally with increasing temperature above 2.0 MPa H 2 in the same way as the other RFe 2 . HIA and precipitation of ErH 2 occurred simultaneously in 1.0 MPa H 2 . On the contrary, hydrogen absorbed crystalline (c-) ErFe 2 H 3.6 decomposed directly into ␣-Fe + ErH 2 below 0.5 MPa H 2 without formation of an amorphous phase. A reason why HIA is observed above the critical hydrogen pressure is discussed on the basis of the hydrogen content in crystalline c-ErFe 2 H x .