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Metallurgical investigations such as recrystallization, martensitic transformation and dynamic behaviors of dislocations have been carried out with a 500 kV electron microscope. The critical foil thickness sufficient to observe the same dynamic behaviors of these phenomena as occurred in bulk specimens is about 1 µ for recrystallization in aluminum and iron alloys, and 3 µ for cell formation in aluminum. On the other hand, foil thickness which allows observation with the 500 kV electron microscope is practically above 8 µ for annealed aluminum and above 2 µ for annealed iron and copper, and it is about one half in order to allow continuous observation of the dynamic behaviors of phenomena. It is concluded that the 500 kV electron microscope has great advantages for the dynamic investigations of metals, especially of materials with the atomic number smaller than 15 such as aluminum and many of ionic crystals.

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simulation study of transformation textures has been conducted on martensitic steels transformed from rolled austenite. A new variant selection concept, called as Bain Strain (BS) model, has been proposed: i.e., such a transformation variant is selected that the generation of Bain strain is most effectively assisted by the rolling stress. Transformation textures simulated in this way have been successfully utilized to explain typical Fe-Ni textures experimentally determined by other authors; with this model, the deformation induced transformation textures presented by Grewen et al. have been satisfactorily reproduced by a simulation under a compressive stress during rolling, and the texture of martensite transformed after rolling reported by Abe et all has been simulated in terms of an internal stress state in rolling. The merits of BS model are discussed in comparison with the existing models. Certain possibilities of the texture control of steels are pointed out for applications in thermomechanical rolling process.