A comparative study in AA4006 alloy strips produced by twin roll caster and direct chill processes: microstructure and crystallographic texture

A comparative microstructural study has been performed in AA4006 alloy strips produced by two industrial casting processes: twin roll caster (TRC) and direct chill (DC). Polarized optical microscopy, scanning electron microscopy, electrical conductivity measurements and Brinnel hardness tests were used for microstructural characterization. X-ray diffraction was used for texture characterization. Significant differences in the morphologies and distributions of the grains and intermetallic particles were detected and are discussed herein. The crystallographic texture throughout the thickness of these strips was determined and the results presented significant differences. Texture analysis was carried out using the X-ray diffraction technique. The twin roll caster (TRC) sheet presented a typical shear texture near the surface, while internally, the beta-fiber was observed.