Macrotexture and microtexture evolution in cold rolled non-oriented electrical steel sheets during annealing

Abstract

Texture evolution in cold rolled non-oriented electrical steel sheets during annealing has been investigated using both electron backscatter diffraction (EBSD) microtexture and macrotexture sampling strategies. The comparison between macrotexture and microtexture pole figures showed that a reliable orientation distribution is obtained if a sampling strategy which acquires data from a sufficiently large number of grains, i.e. using a step size of the order of the grain size, is used. On the other hand, step sizes much smaller than the grain size must be used to generate an orientation map which reveals the microstructure morphology. The texture measurements showed that deformed bands in cold rolled sheets have strong orientations of {100}<011>, {111}<011>, {211}<011> and {311}<011>, i.e. on the α fibre. During annealing at 800°C, recrystallisation occurred. The deformed bands in which the rolling direction was far away from <110> were consumed initially during recrystallisation. In contrast, the α fibres remained to be consumed last. Grain growth occurred after annealing at 900°C.