X-ray diffraction topography and diffuse scattering techniques applied to study the defect structure of plastically deformed al single crystals

X-ray diffraction topography and diffuse scattering techniques were used to study the defect structure formation of plastically deformed Al single crystals. The investigated X-ray scattering has been found out materially to depend upon the character of the dislocation structure (upon the geometry of the dislocation distribution). This dependence is manifested in different distribution of the intensity and in the changed form of the isointensity curves of diffuse and regular (Laue) reflections. In spite of the fact that the distribution of the internal stresses acting in different glide systems under conditions of uniaxial stretching is of complicated character, it is possible to trace the development of the glide process in the body of a sample and to obtain satisfactory interference patterns both of regular reflexions (on topograms) and of diffuse ones (on Laue photographs) up to severe deformations of a crystal at 300, 4.2, and 1.6 K. The following diffuse effects connected with structural changes in deformed crystals have been ascertained on the X-ray photographs:

• —diffuse regions are elongated in the reciprocal lattice space along the glide directions or other crystallographic directions;
• —these diffuse regions are split into separate areas along the directions of the said elongations;
• —the diffuse regions are changed in length: the diffuse reflexes are diffused or condensed;
• —the diffuse scattering isointensity curves are “zigzag”-shaped.