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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.

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.