In this work, a Fe23Mn0.3C1Al high manganese twinning-induced plasticity (TWIP) steel is subjected to varying warm rolling procedures in order to increase the yield strength and maintain a notable ductility. A comprehensive material characterization allows for the understanding of the activated deformation mechanisms and their impact on the resulting microstructure, texture, and mechanical properties. The results show a significant enhancement of the yield strength compared to a fully recrystallized Fe23Mn0.3C1Al steel. This behavior is mainly dominated by the change of the active deformation mechanisms during rolling. Deformation twinning is very pronounced at lower temperatures, whereas this mechanism is suppressed at 500 °C and a thickness reduction of up to 50%. The mechanical properties can be tailored by adjusting rolling temperature and thickness reduction to desired applications.

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Iron–silicon alloys with up to 6.5 wt.% Si offer an improvement of soft magnetic properties in electrical steels compared to conventional electrical steel grades. However, steels with high Si contents are very brittle and cannot be produced by cold rolling. In addition to solid solution hardening, it is assumed that the B2- and DO3-superlattice structures are responsible for the poor cold workability. In this work, two cast strips with 6.0 wt.% Si were successfully produced by the twin roll strip casting process and cooled differently by secondary cooling. The aim of the different cooling strategies was to suppress the formation of the embrittling superlattice structures and thus enable further processing by cold rolling. A comprehensive material characterization allows for the understanding of the influence of casting parameters and cooling strategies on segregation, microstructure and superlattice structure. The results show that both cooling strategies are not sufficient to prevent the formation of B2- and DO3-structures. Although the dark field images show a condition which is far from equilibrium, the achieved condition is not sufficient to ensure cold processing of the material.

Herein, an alloy with 4.5 wt% Si is produced by twin‐roll casting and processed into a crack‐free electrical steel by warm rolling and final annealing. A comprehensive material characterization allows insight into the solidification structure, Si segregation, the microstructure, and texture evolution during the process chain, as well as into the soft magnetic properties of the produced electrical steel. A weak but favorable θ‐fiber is formed by twin‐roll casting and appears again in the final annealed state. Despite the high Si content, this leads to relatively high polarization values. Nevertheless, the expected low iron losses of the Fe–4.5Si alloy cannot be verified, which is probably related to impurities, insufficient flatness, and inhomogeneous grain size distribution.

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