Absorption of hydrogen by LaNi5, NdCo5 and ErCo3 at low temperatures

The rates of hydrogen absorption for activated specimens of LaNi5, NdCo5 and ErCo3 were measured in the temperature range 77 - 300 K. Measurement by a sensitive inductance bridge technique indicated that absorption does not occur at 77 K. Temperatures greater than 140 K are required to initiate hydrogen absorption. The susceptibility of these alloys to poisoning by trace gases at low temperatures prevented the determination of absolute absorption rates. These data are consistent with NMR diffusion studies of hydrogen in LaNi5 hydride. (Auth.)