Structure and property evolution during drawing and wall ironing of aluminum alloy 3004

The evolution of mechanical properties and dislocation substructure during the commercial-scale can making (deep drawing, wall ironing, and “baking”) operations of the aluminum alloy 3004 H19 has been investigated. At each stage the samples were obtained from the deep-drawn cup or wall-ironed can wall and subjected to tensile tests and transmission electron microscopy characterization. The strength decreased (and ductility increased) during deep drawing and increased during wall ironing. The “sizing” of can wall during drawing superimposes a strain hardening effect on these strength and ductility variations. The corresponding changes in dislocation density and cell or microband boundary configuration were observed at each stage. The strain localization and microstructural inhomogeneities were particularly prevalent in the upper parts of the cup and can wall. The cell size and bank thickness did not vary significantly during can making.