Modeling of rolling texture development in a ferritic chromium steel

The development of crystallographic texture during rolling of a ferritic chromium steel containing 11 pct Cr was examined experimentally as well as by polycrystal modeling at large strains (up to 90 pct thickness reduction). The initial shape of the grains was very much elongated in the direction of rolling. A strong rolling direction (RD) fiber (<110> parallel to the rolling direction) has been observed at large strains in the experiment. The Taylor viscoplastic model, the relaxed-constraints pancake model, and the self-consistent viscoplastic approach were employed to simulate the texture development. Strain hardening was accounted for by microscopic hardening laws, for which the parameters were obtained from uniaxial tensile tests. It has been found that among the three models considered, the self-consistent viscoplastic model (the version tuned to finite-element results) yielded the best agreement with the experimentally observed texture evolution. Strong effects of grain shape and hardening have been found. The pancake model was also able to reproduce the main characteristics of the texture because of the flattened initial grain shape.