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Two of the authors found that {011} fiber texture formed at the early stage of the deformation was gradually replaced with {001} fiber texture with increasing strain in Al-Mg alloys at high temperature compression deformation.1) The texture transition proceeded by the preferential growth of grains having {001} fiber texture components.2) It was concluded that the growth of {001} grains was attributed to the low stored energy relating to low Taylor factor as well as the uniform distribution of dislocations due to solute atmosphere, and the stability of this orientation for uniaxial compression.3) It is expected that the mechanism works irrespective of the kind of alloys and crystal structures. Namely, the similar texture formation behavior in which the preferential grain growth plays an important role might occur in other solid solution alloys. In the case of BCC metal, orientations stable for uniaxial compression are {001} and {111}. In the case where the deformation is driven by pencil glide, Taylor factor for {001} and {111} is 2.121 and 3.182, respectively, according to Rosenberg et al. 4) Thus, it is expected that {001} appears as the main component of texture at high temperature compression.In this paper, texture formation during high temperature uniaxial compression is studied on Fe-3mass%Si solid solution alloy with BCC structure. It is found that the strong {001} fiber texture develops at high temperature uniaxial compression deformation. Microstructure observation suggests that {001} fiber texture in Fe-3%Si alloy is also derived from the preferential growth of {001} oriented grains, which coincides with the understanding proposed before.3)Fe-3mass% Si hot rolled plate provided by Nippon Steel Corporation was cold rolled (40%) and annealed for 30 minutes at 1 173 K. The annealing resulted in the equiaxed grain structure with the average grain size of 573 μm and nearly random distribution of crystal orientations.Cylindrical specimens with a diameter of 12 mm and a height of 18 mm, or with a diameter of 10 mm and a height of 15 mm were prepared from the plate. Uniaxial compression tests were conducted up to -1.0 in true strain with constant crosshead speed condition. Temperatures and initial strain rates for the tests were ranging from 1 023 K to 1 173 K and 4.6×10 , respectively. An infraredray furnace was used for heating. After the deformation, the furnace was immediately opened and the specimen was taken out for the cooling in ambient air.The compressed specimen was cut parallel to the compression plane and ground by emery papers in order to obtain the plane of thickness-center. X-ray texture measurement by Schulz reflection method followed by ODF calculation by Dahms-Bunge method 5) and EBSD measurement were conducted on this plane. Pole densities in the inverse pole figures derived from ODF calculation were normalized by the average densities.As well known, the typical deformation texture of BCC metals for uniaxial compression is {001}+{111} double fiber texture at room temperature, in which both ...

Uniaxial compression tests were conducted on Al-3 mass%Mg alloy and Al-3 mass%Mg-0.2 mass%Sc alloy under various amounts of strain and strain rate at 723 K. High temperature yielding phenomena were observed at 723 K and strain rates ranging from 1:0 Â 10 À4 s À1 to 5:0 Â 10 À3 s À1 . Texture examination elucidated that fiber textures were constructed in all the deformation conditions. Texture measurement revealed that the main component of the fiber texture changed from f011g þ f001g to {001} with an increase in strain when the viscous motion of dislocation is the dominant deformation mechanism in the binary alloy. Texture changes are also seen at strength of the {001} component in the binary alloy that increased with increase in strain rates between 5:0 Â 10 À4 s À1 and 5:0 Â 10 À3 s À1 up to a strain of À1:0, while in the ternary alloy, neither variation of the pole density at (011) nor (001) in inverse pole figure is observed in the same deformation conditions. It is considered that Al 3 Sc precipitates contribute to the suppression of grain boundary migration. This means that the grain boundary migration contribute to the development of {001} fiber texture.

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