The hydrogen solubility properties were investigated with the aim of develo
ping hydrides of Ti based alloys for hydrogen storage applications. The hyd
rogen absorption characteristics and the thermodynamics of the dissolved hy
drogen in Ti0.42Zr0.08Fe0.50 were investigated in the ranges 0 less than or
equal to P/bar less than or equal to 40 and 323 less than or equal to T/K
less than or equal to 473 by pressure reduction method and compared with Ti
Fe and Ti0.45Fe0.45B0.1. The hydrogen intake capacity at any particular tem
perature and hydrogen equilibrium pressure is larger in the a phase of Ti0.
42Zr0.08Fe0.50-H compared to that in TiFe-H and nearly the same in the beta
phase. The plateau pressure in Ti0.42Zr0.08Fe0.50-H at any temperature is
slightly higher than that in TiFe-H. The absolute values of the relative pa
rtial molar enthalpy and entropy of the dissolved hydrogen in Ti0.42Zr0.08F
e0.50-H are comparable to TiFe-H. The relative partial molar enthalpy and e
ntropy of hydrogen absorption decreases with the increase of hydrogen conte
nt in the a phase of Ti0.42Zr0.08Fe0.50-H and more or less remain constant
in the alpha + beta phase. (C) 1999 International Association for Hydrogen
Energy. Published by Elsevier Science Ltd. All rights reserved.