The transformation texture in hot-rolled steel sheets has not been quantitatively interpreted based on the rolling or recrystallization textures of γ, although it is well known that the texture in hot-rolled steel should be determined by the texture of y before transformation to a, the KS orientation relationship between γ and a, and the variant selection rules for the relation. The purpose of this article is to show that the quantitative prediction of the texture in hot-rolled steel may become possible if a novel variant selection rule is taken into account. The selection rule to be introduced is that the o nucleated on high angle grain boundaries in γ prefers to have the KS relation with not only one y grain but also another (or more) adjoining y grain(s). This variant selection rule is directly influenced by the texture of prior γ. To "examine this selection rule, the textures of a and retained y of a hot-rolled 0.2%C-2.5%Mn-1.3%(Si+Al) steel sheet were measured by x-ray. Then the measured a texture was compared with the calculated one from the texture of retained γ by the MODF method combined with the above variant selection rule. The agreement between the measured and calculated a textures is remarkable through the entire orientation space. The untransformation calculation of prior γ textures is also described.
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