Development of dislocation substructures was characterized in an aluminum killed deep drawing quality steel at four different plane strain deformations. At and above 20 % reduction, the most significant substructural feature was micro bands (MBs). MBs appeared as paired dislocation walls of 0.2-0.4 mum thickness and were always at an angle of approximately 37 degrees with rolling direction (RD). As the traces of the MBs were more than 5 degrees of {110} and {112}, closed packed planes of the bcc system,-they were termed as first generation" or non-crystallographic using the convention(16)) commonly used in fcc metals. Other than the pre-deformation high angle boundaries, MBs were the only feature with large enough misorientations necessary for optical visibility. At least for the range of strain and strain path used in the present study, the first generation MBs can be considered as the so-called grain interior strain localizations. Relative presence and effectiveness of MBs were quantified in different microtexture components from the MB spacings along TD (lambda) and the average misorientation across MBs (theta (MB)) and these appear to determine the stored energies of different microtexture components.
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