Dear All: I am working on a bulk, polycrystalline (fcc) material that has multiple deformation faults in the interior of the grains, and has also macroscopic residual stresses. I have the set of positions for the experimental XRD peaks, and I would like to calculate both the magnitude of the residual stress and the lattice parameter. I know that: (1) for the lattice parameter determination I can use the peak positions coupled with the Bragg law and the interplanar spacing equation for cubic system, and (2) I can calculate the residual stress from the interplaner spacing and the Hooke´s law using also an stress-free material.
My question is: Should I correct firstly the experimentally-determined peak positions by the peak shifting induced by the deformation faults (as described in the Warren´s book for fcc crystals) to obtain so a new set of "corrected" peak positions and then using this "corrected" set to compute the lattice parameter and residual stress?, or, on the contrary, Should I calculate the lattice parameter and residual stress directly from the peak positions with no peak-shifting correction by deformation faulting?. Thanks in advance. Angel
