Fourier analysis of X-ray micro-diffraction profiles to characterize laser shock peened metals

X-ray micro-diffraction profiles using a synchrotron light source were analyzed via Fourier transformation for single crystal Aluminum and Copper samples subjected to micro-scale laser shock peening. Specifically, the asymmetric and broadened diffraction profiles registered across the shock peen region were observed and analyzed by classic Warren and Averbach (W–A) method [Warren, B.E., Averbach, B.L., 1950. The effect of cold-work distortion on X-ray patterns. Journal of Applied Physics 21, 595–599] and modified W–A method [Ungar, T., Borbely, A., 1996. The effect of dislocation contrast on X-ray line broadening: A new approach to line profile analysis. Applied Physics Letters 69, 3173–3175]. Average strain deviation, mosaic size and dislocation density were estimated for the first time with a spatial resolution of 5lm. The results compare well with the simulation results obtained from FEM analysis and from electron backscatter diffraction (EBSD) measurements. Differences in response caused by different materials and crystalline orientations (110 and 0 01) were also studied.