Texture evolution in the Fe-30.5Mn-8.0Al-1.2C and Fe-30.5Mn-2.1Al-1.2C steels upon cold rolling

Abstract

Crystallographic textures of the austenitic low-density Fe-30.5Mn-8.0Al-1.2C (8Al) and Fe-30.5Mn-2.1Al-1.2C (2Al) (wt.%) steels were examined during cold rolling by means of electron backscatter diffraction (EBSD) and electron channeling contrast imaging (ECCI). Random oriented grains orient towards Goss- and brass-components along the α-fiber as the strain increased, with activation of slip, mechanical twinning, and shear banding, for both steels. S- and copper-orientations were also observed in the 8Al steel at 50% reduction. The route of Cu-CuT-Goss-brass texture evolution was found in the 2Al alloy. Cu, Goss, and brass textures occur as a dominant texture in the deformed 8Al alloy. Copper-type texture accompanied with slip at low reduction (20%), as well as Cu-type shear bands, and shear banding inside Goss-oriented grains at higher reduction (50%), were observed in the 8Al steel. It is suggested that this copper-type rolling texture may be attributed to the Al addition, which contributes to its low twinning activity compared to that in the 2Al alloy. Cu-CuT-brass f.c.c. rolling texture transition to form the Brass-type texture was observed at higher reduction in the 2Al alloy with strong similarity to that found in other Fe-Mn-C system TWIP steels.