MECHANISM OF DEUTERIUM CRACKING IN PALLADIUM

After 290 h electrochemical charging of deuterium,the density of dislocation in well-annealed Pd was increased from 10~8/cm~2 to over 10~12/cm~2 and a large amount of bubble-like voids or cracks was observed by optical and transmission electron microscopes.The mechanism of deuterium cracking is believed due to the formation of molecular De during the segregstion and combination of deuterium atoms around dislocations.XRD results showed that the lattice constant of Pd increased from 0.3890 nm to 0.4034 nm.