Deformation of palladium plates by a small external stress during hydrogen absorption and desorption

We observed an unexpected bending of a horizontally held palladium plate at 150 °C under a small external shearing stress. The deformation was fastest at the nominal composition of PdH0.1−0.2, which is in the α + β phase. We also observed that a plate warped back and forth during a cycle of absorption and desorption of hydrogen when it was hung vertically, which does not have a reasonable explanation.