Rev.Adv.Mater.Sci. (RAMS)
No 2, Vol. 23, 2010, pages 119-125


A.M. Trostianchyn, I.I. Bulyk, I.V. Trostianchyn, S.I. Mudry and V.M. Davydov


Interactions in an La0.5Nd0.5Ni5-xAlx-H2 (x=0.0, 1.0, and 1.5) system were studied by means of differential thermal (DTA) and X-ray phase analyses in a temperature range from room temperature up to 900 °C at the initial hydrogen pressure of 5 MPa. The character of interactions was shown to depend on the chemical composition of the alloy while the phase composition of the interaction products was determined by the conditions of hydrogenation-disproportionation processes. On heating under hydrogen, the La0.5Nd0.5Ni5 alloy was homogenized and textured, while with x=1.0 an Ni3Al intermetallic hydride of a mixture of rare-earth metals and an (La,Nd)(Ni,Al)5Hx hydride with a CaCu5-type structure and a doubled c lattice parameter appeared as the process products. The La0.5Nd0.5Ni3.5Al1.5 alloy completely disproportionated into a lanthanum hydride and an Ni3Al intermetallic. The products of partial and complete disproportionation recombined in vacuum.

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