Hydrogen isotope effects in Ti1.0Mn0.9V1.1 and Ti1.0Cr1.5V1.7 alloys

The hydrogen isotope effects in Ti1.0Mn0.9V1.1 and Ti1.0Cr1.5V1.7 alloys have been investigated at 313 and 353 K and at 313 and 338 K, respectively, using protium and deuterium. The crystal structures including the phase abundance and the lattice parameters were determined by the Rietveld method. Using SEM and EDX, the morphology was examined and an elemental analysis was carried out. In both alloys and regardless of temperature, the amounts of deuterium absorption were larger than those of protium. The hydrogen isotope effects of Ti1.0Mn0.9V1.1 and Ti1.0Cr1.5V1.7 were fairly large in comparison with that of LaNi5. The protide of the Ti1.0Mn0.9V1.1 alloy was more stable than the corresponding deuteride. although at 313 K the equilibrium pressures of deuterium and protium showed slightly opposite behaviour. In the Ti1.0Cr1.5V1.7 alloy, the deuteride was always more stable than the corresponding protide in the experimental temperature range. The Ti1.0Cr1.5V1.7 alloy absorbed more deuterium and protium than the Ti1.0Mn0.9V1.1 alloy. (C) 2000 Elsevier Science S.A. All rights reserved.