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In situ neutron diffraction experiments were performed to follow the annealing behavior of iron deformed by equal-channel angular pressing at room temperature using route Bc to a total von Mises strain of evM = 9.2. The temperature was varied from room temperature to 1223 K (950 °C), while neutron diffraction data for quantitative texture analysis were collected at a given temperature when holding for 5 minutes. Pole figures and orientation distribution function maps from neutron diffraction and electron backscatter diffraction measurements were used to follow the changes in crystallographic texture and grain size during annealing. In situ neutron diffraction experiments allowed understanding and identifying texture-related changes that occur during recrystallization, grain growth, and phase transformation in iron.

The phase transformation of low-carbon steels is evaluated by means of computer simulations performed with a viscoplastic self-consistent (VPSC) code. The simulations allow calculating micromechanical data at high-temperature deformation that are currently inaccessible through experiments. The micromechanical data are later on used in phase transformation computer codes to evaluate the pre-eminence of certain transformation variants following different criteria. The texture results are compared with experimental results available in the literature. The main fibers and components develop and behave differently depending on the selection of hardening laws, fragmentation criteria, active slip systems, etc. The results are compatible with high-temperature textures characteristic of a high stacking fault energy (HSFE)–like alloy and selection of variants based on the activity of the high-temperature slip systems.

A theory of anelasticity is presented, where the relaxation of all the elastic compliances, as a function of orientation, is considered. The theory is developed for cubic and hexagonal crystals. It is shown that, in addition to the usual relaxations of Young's and shear moduli, anelastic phenomena related to the relaxation of Poisson's should be considered, and, an energetic interpretation of the phase lags obtained is given. Finally, some point defect symmetries and particular orientations are considered, as special situations of the general formalism presented.

A theory is developed, based on theoretical-group analysis, to describe the linear, reversible, time-dependent response of an icosahedral quasicrystal, containing point defects, to a stress field and known as anelastic relaxation. We obtain also anelastic relaxation relationships for the practical Young’s, shear and Poisson’s moduli.

Une theorie d'anelasticite des cristaux cubiques et hexagonaux dans laquelle la relaxation des compliances elastiques en fonction de l'orientation est prise en compte et presentee