The anisotropic mechanical properties of steel sheets are mainly controlled by their crystaliographic textures. Until recently, little attention has been paid on the understanding of the textures formation after hot-rolling, which are produced by phase transformation, although it is recognised that they have an effect on the development of the texture in the further process (cold rolling and annealing). Moreover, development of new kind of steels like TRIP steels, which micro structure is formed during phase transformation, makes it particularly important to understand how these textures form and how we can control them. The aim of this work is to contribute to the understanding of the textures resulting from a transformation between the austenite and the ferrite phase. A brief survey of the literature concerning the orientation relationships between these phases is given in the introduction. Then the orientation relationship between gamma and alpha phases and the variant selection phenomenon is investigated in the first part of this work at the scale of individual grains using the EBSD technique. This work is carried out on a TRIP steel, containing both the parent and the product phases, so that a direct link could be established between the orientations of the austenite and of the product phases. The role of active slip systems during the deformation of austenite is also considered. In a second part we examine the macroscopic textures of a low carbon steel for different state of austenite before transformation, namely when it is deformed or recrystallised.
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