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A method to simulate shear effects and through-thickness texture gradients in rolled sheet materials is introduced. The strain history during a rolling pass is idealized by superimposing a sine-shaped evolution of the 13 shear component to a plane-strain state. These generic strain histories are enforced in a visco-plastic self-consistent (VPSC) polycrystal deformation model to simulate texture evolution as a function of through-thickness position. The VPSC scheme is deemed superior to a full constraints (FC) or relaxed constraints (RC) approach, because it allows one to fully prescribe diagonal and shear-strain-rate components while still accounting for grain-shape effects. The idealized strain states are validated by comparison with deformation histories obtained through finite-element method (FEM) calculations. The through-thickness texture gradients are accounted for by introducing a relative variation of the sine-shaped 13 shear with respect to the plane-strain component. The simulation results are validated, in turn, by comparison with typical examples of through-thickness texture gradients observed experimentally in rolled plates and in sheets of fcc and bcc materials.

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In order to study the format ion of ridging in ferritic stainless steel (FSS) sheets , the evolution of the crysta llographic texture was investigated by macro and micro-textu re meas urements throughout the thickness of the sheets . The as-received hot band material displayed a pronounced through-thickness textu re gradient with a strong rotated cube orientation in the sheet center layer. The initial texture of the hot band had a high impact on the format ion of the cold rolling texture and on the final recrystallization texture . Modification of the cold rolling texture by means of cross-rolling led to an improvement of the macro and micro-textures after final recrystall ization annealing, which gave rise to an enhanced sheet formability in FSS . Tensile tests of specimens with half thickness revealed that ridging formed in the sheet center was much stronger than that in the surface . This observation was attributed to the more frequent formation of orientation colonies in the sheet center when compared to the sheet surface.