Mechanical properties of packed bed of hydrogen storage alloys in loading and unloading processes

This study investigated the mechanical properties of a packed bed of hydrogen storage alloy before and after hydrogen absorption/desorption. As a result, it was found that the initial packing ratio decreases with an increase in the number of absorption/desorption cycles. During the loading process, the packing structure changed more for a packed bed with lower packing ratio, and the tangent modulus increased, whereas the structure changed little during the unloading process. Further, the compression behavior was almost elastic when the packed bed was loaded again.