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The residual lattice strain, the crystallite size, the components of Gaussian and Cauchy functions of the X-ray line profile, determined by the Fourier analysis, are correlated for a better understanding of microstructural characteristics of a coarse and fine Y−Ba−Cu−O powder after explosive consolidation. The results are discussed taking into account the lattice defects generation, in particular, the twin formation in different crystallographic directions after shock loading.

The residual lattice strain, the crystallite size, the components of Gaussian and Gauchy functions of the line profile, determined by Fourier analysis, are correlated for a better understanding of recovery and recrystallization phenomena of Cu annealed after fast and conventional deformations. The density and distribution of the dislocations in the deformed starting material strongly influence the mechanisms of intermediate and high-temperature recovery as well as those of primary recrystallization.

The residual lattice strain and the crystalline size determined by Fourier analysis were measured for a better understanding of the mechanical properties of an ultralightweight metal matrix composite. An oriented SiC whisker reinforced aluminum alloy composite was examined. The microstructural characteristics were evaluated along different directions. Microhardness tests were carried out and correlated with the distribution and density of the microstructural defects.

The crystallite size, the residual lattice strain, the components of Gaussian and Cauchy functions of the line profiles obtained by Fourier analysis of X-diffraction lines, are correlated for a better knowledge of mechanical properties of infiltrated composites with ceramic reinforcements of different volume fractions (27, 19, 10%) and types (SiC whiskers, Al2O3 fibers and particles) after fast and slow deformation. The results are discussed taking into account the role of the reinforcing phase on the generation and relocation of dislocations along different crystallographic directions (111,200,220).

Comparative examinations have been carried out on Al and ERGAL specimens deformed by compression either fast or slow. The high-strain-rate compressions were obtained by explosive. The dislocation structures have been examined by transmission electron microscopy and by Fourier analysis of the X-ray diffraction lines. Crystalline textures were also determined. After fast deformation smaller interaction energies appear among the dislocations with comparable total densities because of the accumulation in grain boundaries. The results have been interpreted by assuming that the loads which are reached in the shock and reflected wave fronts give rise to generations or multiplications of the dislocations on levels more differentiated than by slow compression.