Cube texture formation in high purity aluminum foil for electrolytic capacitor was investigated by X-ray diffraction and optical microscopy. In addition to one step of partial annealing and light rolling process, one or two more steps of the process lead to the formation of the more intense cube texture than by the one step. Simultaneously, as the cycles of partial annealing and light rolling increase, formation of R-orientation grains is suppressed. Optimum condition of second and third partial annealing and light rolling for the formation of strong cube texture was determined. It was confirmed by slip trace experiments that cube grains formed at second partial annealing grow preferentially during final annealing after second light rolling. Strong cube texture formation was ascribed to the ease of recovery in rolled cube grains and their preferential growth at the expense of un-recrystallized region.

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In order to control orientation distributions or texture in polycrystalline materials, it is important to study microstructural evolution, such as recrystallization and grain growth. In this study, microstructures have been observed in detail by using the SEM/EBSP orientation analyzing system before and after annealing during grain growth in an aluminum foil for electrolytic capacitor. The foil sample after the first annealing had a columnar structure with a few R-orientation grains in a cube texture. It was found that some grains disappeared after the second annealing. We carried out Monte Carlo simulation of grain growth in the Potts model applying orientations image data before the second annealing to an initial microstructure to predict microstructural evolution. Dependence of grain-boundary energy on misorientation was given on the basis of previous experimental knowledge in the simulation model. The simulation reproduced migrations in high angle grain-boundaries with disappearing of R-orientation grains and stable topological features in low angle grain-boundaries.

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In an attempt to refine the grain structure of 200 mm wide sheets of the 7475 based aluminum alloy including Zr, a new warm rolling method under the control of both roll temperature and material temperature was used. The warm rolled sheet as solution-heat treated had a subgrain structure through the thickness with a high proportion of low angle boundary less than 15°. The average subgrain diameter was approximately 3 μm. The strength of the warm rolled sheet in T6 condition was about 10% higher than that of a conventional 7475 alloy sheet produced by cold rolling. As the most remarkable point, a high Lankford value (plastic strain ratio of width to thickness) of 3.5 was observed in the orientation of 45° to rolling direction, with the average Lankford value of 2.2. It was thought that the high Lankford value should be brought by well developed β–fiber, especially with the strong {011}<211> brass component. The warm rolled sheet also had a good resistance to SCC. From Kikuchi lines analysis and TEM images, it was found that PFZ was hardly formed along the low angle boundaries of the warm rolled sheet in T6 condition. This should be a factor to lead the improved resistance to SCC because of reducing the difference in electrochemical property between the grain boundary areas and the grain interior.

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Mg–3%Al–1%Zn (AZ31) alloy was subjected to ECAE (Equal Channel Angular Extrusion) processing under various processing conditions in order to reveal the effect of the microstructural parameters on tensile properties of magnesium alloy. Then tensile tests were carried out at room temperature to investigate the relationship between tensile properties and microstructural parameters including the texture generated by ECAE processing and grain size. As a result, in 4–pass ECAE specimens processed at 250°C, tensile ductility is improved as a result of basal slip that occurs easily when tensile test was performed along the extrusion direction, because such specimens have textures in which the basal plane is inclined at 45° to the extrusion direction. On the other hand, in the specimens processed at 300°C, which have textures in which the basal plane is oriented parallel to the extrusion direction, 0.2% proof stress is higher than those of specimens processed at lower temperatures, but elongation is smaller because basal slip is difficult to occur. However, 8-pass specimens processed at 200°C and annealed, which have similar texture but different grain sizes (d) exhibit clear grain size dependencies of 0.2% proof stress (σ_0.2) according to Hall-Petch relationship; σ_0.2 = 30 + 0.17d^−1⁄2. Therefore, crystallographic orientation has a profound effect on the tensile properties of AZ31 alloy, and grain size also has a little effect.

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Changes in microstructure and crystallite orientation distribution by continuous cyclic bending (CCB) and the subsequent annealing have been investigated in a commercial purity titanium. The sheet of the titanium worked by CCB with less dimensional change showed 1.3 times higher hardness than that before CCB on the surface. The CCB and the annealing formed the gradient microstructure with coarse-grained surface layers and fine-grained inside. Thickness of the coarse-grained layers could be controlled by the CCB process conditions. It was found that the transverse texture (TD//[0001] )appeared after the CCB and annealing in the surface layers.

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