Hydrogen absorption properties of Ti[sbnd]Cr[sbnd]A (A ≡ V, Mo or other transition metal) B.C.C. solid solution alloys

Abstract

The pressure-composition isotherms (P-C-T) for hydriding of TiCr binary alloys and TiCrA (A ≡ V, Mo or other transition metal) ternary alloys with b.c.c. structures were measured to examine the effect of the composition on the hydrogen-absorbing capacity and equilibrium dissociation pressure.In the TiCr binary system two plateau regions were recognized in the P-C-T curves as in other b.c.c.-type alloys. The TiCr alloy with 33 at.% Ti (Ti33Cr67) shows the best P-C-T characteristics in the TiCr binary system, although the maximum hydriding capacity is lower than in alloys with a large Ti content. The maximum absorbing capacity was increased by the addition of V or Mo to the Ti33Cr67 b.c.c. alloy. After 1000 absorption-desorption cycles the hydriding capacity of the TiCrV (Ti33Cr33V33) b.c.c. alloy decreased to 70% of the initial capacity. The TiCrV b.c.c. solid solution alloy has excellent resistance to pulverization campared with intermetallic compounds.