Transformation mismatch plasticity in Pd induced by cyclic hydrogen charging

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

“…[19], but the direction of stress in our experiment was different from other experiments; in ordinary superplasticity experiments one applies tension to a metal, but the plate experienced shearing stress in our experiment. This should be one of the reasons we observed much larger elongation rate than Beeri et al's result [17], 5 × 10 −7 s −1 . Another factor is the hydrogen absorption rate due to the difference in the temperature, 20 minutes in Experiment B1 and 10 hours in Ref.…”

“…[17] Their experiment was conducted under room temperature and showed the result consistent with Ref. [14] in the sense that they observed elongation during the absorption and shrinkage after one cycle of absorption and desorption of a wire when the stress on it was relatively small.…”

“…The magnitude of the stress was smaller by a factor of from 100 to 1000 than the stress applied in Ref. [17]. The importance of the direction of the stress is also true to Experiment B2, for it has fastest elongation rate of 8.7 × 10 −7 s −1 that is comparable to that in Ref.…”

“…Another factor is the hydrogen absorption rate due to the difference in the temperature, 20 minutes in Experiment B1 and 10 hours in Ref. [17], but the stress in the different direction has a large effect. The magnitude of the stress was smaller by a factor of from 100 to 1000 than the stress applied in Ref.…”

Hydrogen-induced plasticity in nanoporous palladium

“…On the other hand, an additional driving force for compressive deformation due to the nanoporous structure itself and its surface excess energy is present in the sample. An effect called internal-stress plasticity (ISP), also commonly known as transformation plasticity, is well established in the literature [42–45]. A schematic representation of the transformation-mismatch plasticity mechanism in npPd is presented in Fig.…”