Papers by Author: Ludger Lahn

Abstract: A silicon steel single crystal with initial Goss orientation, i.e. the {110}<001> orientation, was cold rolled up to 89 % thickness reduction. Most of the crystal volume rotates into the two symmetrical equivalent {111}<112> orientations. However, a weak Goss component is still present after high strain, although the Goss orientation is mechanically instable under plane strain loading. Two types of Goss-oriented crystal volumes are found in the highly deformed material. We suggest that their origin is different. The Goss-oriented regions that are observed within shear bands form during the cold rolling process. In contrast, those Goss-oriented crystal volumes that are found inside of microbands survive the cold rolling.

Abstract: A silicon steel single crystal with {110}<001> Goss orientation was cold rolled up to 89 % thickness reduction and subsequently annealed. The evolution of the macroscopic cold rolling texture was investigated by x-ray diffraction. Local orientation relationships and the microstructure around and within Goss grains of deformed and annealed samples were analysed using the electron backscatter diffraction (EBSD) technique. During cold rolling a texture consisting of two strong {111}<112> components and a minor {110}<001> Goss component develops. After primary recrystallisation the texture is characterized by a strong Goss component. Goss-oriented grains that remain after high deformation are considered to be the origin for the primary recrystallisation texture.