Study of microstrain and stress in non-planar palladium membranes for hydrogen separation

MicroXRD measurements were performed to evaluate the effect of the stress-relief heat treatment, carried out for different time and temperatures on Palladium layers of tubular membranes used for hydrogen separation. Since residual stresses were not detected, the FWHMs were evaluated by the integration of the Debye rings and the microstrains calculated by the Williamson-Hall (W-H) equation. After the normalization for the elastic anisotropy (altered W-H analysis), the data showed a very good linear behaviour. The evolution of Pd microstructure was also studied and the best thermal profile for the heat treatment of the Palladium membranes was found.