MWP-fit: a program for multiple whole-profile fitting of diffraction peak profiles by ab initio theoretical functions

A computer program has been developed for the determination of micro-struct ural parameters from diffraction profiles of materials with cubic or hexago nal crystal lattices. The measured profiles or their Fourier transforms are fitted by ab initio theoretical functions for size and strain broadening. In the calculation of the theoretical functions, it is assumed that the cry stallites have log-normal size distribution and that the strain is caused b y dislocations. Strain and size anisotropy are taken into account by the di slocation contrast factors and the ellipticity of the crystallites. The fit ting procedure provides the median and the variance of the size distributio n and the ellipticity of the crystallites, and the density and arrangement of the dislocations. The efficiency of the program is illustrated by exampl es of severely deformed copper and ball-milled lead sulfide specimens.