The density and the character of dislocations in cubic and hexagonal polycrystals determined by X-ray diffraction

The density and the character of dislocations in cubic and hexagonal polycrystals were determined by a new procedure of X-ray diffraction profile analysis. The anisotropic strain broadening of diffraction profiles was accounted for by dislocation contrast factors. The screw or edge character of dislocations in a severely deformed copper specimen was determined by analysing the dislocation contrast factors. Comparing the contrast effect of the possible dislocation slip systems in hexagonal crystals with that determined experimentally for a sintered tungsten carbide sample, it was found that the dominant slip system in this specimen is 〈112̄0〉{0001}. The dislocation density was calculated for both samples by the modfied Warren–Averbach procedure.