Deformation of Palladium Plates by a Small Stress during Hydrogen Absorption and Desorption

TL;DR

This study reports unexpected deformation of palladium plates under small stress during hydrogen absorption/desorption, especially near PdH0.1-0.2 composition, with unusual cyclic warping observed without clear explanation.

Contribution

It reveals novel deformation behaviors of palladium under hydrogen cycling, highlighting phenomena not previously documented in the context of small external stresses.

Findings

Fastest deformation at PdH0.1-0.2 composition

Cyclic warping during hydrogen absorption/desorption

Deformation occurs under small external stress

Abstract

We observed an unexpected bending of a horizontally held palladium plate at 150$^{\circ}$C under a small external shearing stress. The deformation was fastest at the nominal composition of PdH$_{{\rm 0.1-0.2}}$, which is in the $\alpha+\beta$ phase. We also observed that a plate warped back and forth during a cycle of absorption and desoprtion of hydrogen when it was hung vertically, which does not have a reasonable explanation.