Effect of rolling reduction on antiphase domains, grain boundary character distribution and plastic deformation of Fe-6.5 wt%Si alloy

[Display omitted] •Investigation of APD and GBCD on plastic deformation of Fe-6.5 wt%Si.•APD sizes decrease with increasing rolling reductions.•γ-Fiber texture is beneficial to obtain more CSL boundaries.•More CSL boundaries occur in high rolling reduction.•High rolling reduction improves plastic deformation ability. The variation in plastic deformation of Fe-6.5 wt%Si alloy depends on antiphase domains and grain boundary character distribution. With the increase of rolling reductions from 50% to 85%, the increment of dislocation density causes decline of the sizes of antiphase domains, meanwhile the sharp and homogeneous distribution of γ-fiber texture is prone to obtaining a large fraction of CSL boundaries, thus the fracture deflection of 65% warm-rolled sheet is increased to 8.6 mm by 38.7% in comparison to that of 50% warm-rolled sheet (6.2 mm), and that of 85% warm-rolled sheet has nearly three times increment (18.2 mm).